The graph you reference (the link btw is faulty) shows a reduction in percentage of students valuing school. I think this will require different reasoning from the concomittant loss in enthusiasm within each student over time, and i would like to attempt to address both issues if i may.

My start points are:

Issue 1, the drop in numbers of students remaining engaged.

The reasons for this are multiple as Laura suggests. I would add that it is an additive effect, the slow, inexorable collection of negative influences within the school environment. Only those students who have high quality motivation can maintain it in the face of the collection of negatives over time.

Issue 2, the progressive loss in engagement/motivation within individuals or groups. The reason i distinguish this is because there are interesting patterns in groups, eg in Australia, the loss in motivation is greatest amongst indigenous and low SES students. My experience, not just general observations as an educator, but also from an action research project i undertook over 5 years where i changed some of the parameters within which the school worked, leads me to focus in particular on schooling parameters that speak to motivational pillars.

A key issue is readings of the meaning of success. Currently, students who, for various reasons, begin school behind the 8 ball socially or educationally are most likely to define themselves as unsuccessful at school from an early age, and soonest lose enthusiasm. So, when i had the opportunity in the A.R., i redefined the meaning of success by altering assessment, reporting processes and teacher language around success. Over the 5 years, i noted greater motivation in class, especially, but not only, amongst the lower achievers. In a nutshell, the definition of success was reframed from 'passing' against criteria, to 'progressing' with effort, a kind of personal best approach. There is much more to say, but hopefully this is enough to get the ideas across.

To your question: while there are multiple reasons for loss in  enthusiasm, the one that is most interesting is self efficacy in schooling. Schooling, that collection of contexts, processes, procedures, relationships and language constructs is not designed well to maintain engagement/motivation because it negatively impacts on self efficacy, mindset, resilience etc. My hypothesis, on the basis of the action research, is that redesigning the processes, procedures, language used in school to positively impact on the student psychology/sociology would see a significant gain in erngagement. Unfortunately, what i think would work is unattractive politically, and hence unlikely to gain traction. That being said, the Australian Council for Educational Research (ACER) is currently looking to change at least some of the parameters, I am describing.

Part of the problem is the older children who show a bad example and bad attitude to the younger children about school in general. But I have found only the best teachers even try to show their students the real-world application of the material they are teaching. When students can't understand why something is important to them or how they can use it to reach their goals (as vague and changeable as they might be), they stop caring about learning and turn to something that pays in more tangible and immediate benefits such as selling drugs or prostitution.

This is only partially from scholarly literature...

(1) Anecdotal: one of my policy branch managers once pointed out, people are so different, but governments insist on a single policy solution for all of them! In public education, we have a strictly transmission-based, achievement model of schooling, and that may not work for all. Individuals are disengaged - or even alienated - for a ton of individual reasons...

(2) Research on student engagement doesn't seem to point to a single answer, but certainly the literature on culturally responsive or culturally sustainable education and pedagogies might point to some of the issues of disengagement, especially as kids get older. This would only be ONE reasons (structure of the day might be another, absence of supports for overall wellness might be another, etc.). But here is an example by yours truly (references at end - these do not include anything by Ladson-Billings but if you have not read her work, strongly recommended)...

In his eloquent autobiography, celebrated Latino author and professor Richard Rodriguez describes how teachers convinced his parents to only speak English at home so that he would succeed in school – the approach was to integrate or assimilate him into Euro-centric culture.  While the switch to English led to school (and later career) success, Rodriguez lost a great deal in the process.  As he lost his fluency in Spanish, and as English became the language of the Rodriguez family, the special feeling of closeness is diminished.  When his days became devoted to understanding the meaning of words, Rodriguez no longer heard intimate family voices.  His Spanish-speaking home was a noisy, playful, warm, and emotionally charged environment; his English-speaking household was quiet and restrained (Martin, 1985). Despite academic and professional success, the integration led to profound alienation.

Patrina Duhaney (2010) and Vershawn Ashanti Young (2010), who both self-identify as Black, talk about the alienation they experienced when they did well in school in high school as well as college. Both were accused of “acting white” by Black peers, while at the same time being pressured to conform to the Euro-centric ways of schooling by teachers and white peers. They discuss how they struggled to negotiate their racial identities to achieve academic success.  Young says, “the more I acted white, the more I seemed to succeed” (Young, 2010, p. 702). He describes his discomfort with “race switching” – which he continued to do as a high school teacher and later an English professor. When hired to teach in a high school, he believed that his employers wanted him to teach racialized students how to “race-switch” into the dominant way of schooling, but he found himself more interested in “teaching white kids out of the racism I saw in them” (p. 708). This left Young, like Duhaney, in a constant state of tension.

Stories like those of Richard Rodriguez, Patrina Duhaney and Vershawn Ashanti Young are reflected in a lot of large-scale research. Approximately 40% of US high school students report that that they have little or no interest in school (McInerney, 2009). Alienation is most prevalent among for boys and low achieving students (Hascher & Hagenauer 2010). In most cases, alienation from school increases during adolescence, and is affected by instructional quality, teacher-student relationships, and student-student relationships (Hascher & Hagenauer 2010), as well as feelings of powerlessness and a disconnection between the curriculum and students’ values, cultures and lives (McInerny, 2009; Williams, 2008). In short, alienation happens when school is culturally un-responsive and relationships between students and school are minimal.

Duhaney, P. (2010). Why is our educational system still guilty of whiteness?  Canadian Social Work Review, 27, (1), 95-113.

Hascher, T. & Hagenauer, G. (2010). Alienation from school. International Journal of Educational Research, 49(6), 220-232.

Martin, J. R. (1985). Becoming educated: A journey of alienation or integration? Journal of Education 67(3), 71-84.

McInerney, P. (2009). Toward a critical pedagogy of engagement for alienated youth: Insights from Freire and school-based research. Critical Studies in Education, 50(1), 23-35.

Williams, A.D. (2008). Re-membering Freire: The links between hip-hop culture and Paulo Freire. Journal of Thought, 43(1/2), 71-85.

Young, V.A. (2004). Your average nigga. College Composition and Communication, 55(4), 693-715.

The graph you reference (the link btw is faulty) shows a reduction in percentage of students valuing school. I think this will require different reasoning from the concomittant loss in enthusiasm within each student over time, and i would like to attempt to address both issues if i may.

My start points are:

Issue 1, the drop in numbers of students remaining engaged.

The reasons for this are multiple as Laura suggests. I would add that it is an additive effect, the slow, inexorable collection of negative influences within the school environment. Only those students who have high quality motivation can maintain it in the face of the collection of negatives over time.

Issue 2, the progressive loss in engagement/motivation within individuals or groups. The reason i distinguish this is because there are interesting patterns in groups, eg in Australia, the loss in motivation is greatest amongst indigenous and low SES students. My experience, not just general observations as an educator, but also from an action research project i undertook over 5 years where i changed some of the parameters within which the school worked, leads me to focus in particular on schooling parameters that speak to motivational pillars.

A key issue is readings of the meaning of success. Currently, students who, for various reasons, begin school behind the 8 ball socially or educationally are most likely to define themselves as unsuccessful at school from an early age, and soonest lose enthusiasm. So, when i had the opportunity in the A.R., i redefined the meaning of success by altering assessment, reporting processes and teacher language around success. Over the 5 years, i noted greater motivation in class, especially, but not only, amongst the lower achievers. In a nutshell, the definition of success was reframed from 'passing' against criteria, to 'progressing' with effort, a kind of personal best approach. There is much more to say, but hopefully this is enough to get the ideas across.

To your question: while there are multiple reasons for loss in  enthusiasm, the one that is most interesting is self efficacy in schooling. Schooling, that collection of contexts, processes, procedures, relationships and language constructs is not designed well to maintain engagement/motivation because it negatively impacts on self efficacy, mindset, resilience etc. My hypothesis, on the basis of the action research, is that redesigning the processes, procedures, language used in school to positively impact on the student psychology/sociology would see a significant gain in erngagement. Unfortunately, what i think would work is unattractive politically, and hence unlikely to gain traction. That being said, the Australian Council for Educational Research (ACER) is currently looking to change at least some of the parameters, I am describing.

Mark - thank you for such a thorough response - I enjoyed it immensely and you offer some excellent insight.

I think that Robin's original question had to do with "enthusiasm" - so that may not constitute achievement. I have a point with the stories that follow - and it has to do with the distinction between types of engagement, and also the fact that the same level of social capital doesn't necessarily translate to the same levels of achievement or results. 

Here's an interesting example: my brother was a student who truly enjoyed going to school. He attended every single day (willingly!), and scored very high on standardized intelligence tests. However, his grades were always poor, and he was labeled a “class clown” and “trouble-maker”  (I know this is consistent with students classified as gifted - though he was never identified as such and remained in a regular classroom). He also was popular and had lots of friends, which further encouraged him to willingly attend on a daily basis (and probably encouraged his disruptive streak!). Basically, he had a high level emotional engagement in school – it’s a place where he felt safe and very connected to other students. However, he was never behaviorally or cognitively engaged.

I was a completely different story. Unlike my brother, I tended to have very high grades, and always (but reluctantly!) did exactly what the teacher asked even when I disagreed. I found school very stressful, and NOT intellectually stimulating, and I hated attending. As a result, I missed a lot of classes anytime I could convince a parent to phone in for me to give me a day to work at home on various self-directed projects that I convinced them where more worthwhile than class (yes, I invented academic and research projects that had nothing to do with the curriculum even in elementary school). So basically, I had high achievement in terms of grades/tests, and probably high behavioral engagement (at least compliance), but my level of emotional engagement was very low until I started graduate school when that all turned around.

@William - This lack of relevance does point to a dated and relatively weak curriculum , at least in Ontario Canada.  And of course standardized testing doesn't help anyone but the governing powers.

Wow Laura - You have really outdone yourself here (first posting- then I will respond to the second)-  Thank you for the references.  Do you think there would be individual differences in this graph.  Perhaps boys are less enthusiastic than girls and maybe there are cultural differences, although I would not know where to predict there.  I think I would like to do a large scale robust study on this - I tried to follow up on Fullan's reference but found little - so that is one other reason I wouldn't to post to see if others had come across this kind of research or pattern.

@Mark - Thanks so much for this interesting post (the link works now).  So here easily could be individual differences and of course the details are critical - SES, indigenous population, self-efficacy and this list goes on.  I suppose I shouldn't expected a simple set of reasons.  Interesting that you have to resort to action research.  I am sure most educators are not totally surprised by this result - I would have thought there was more research out there.  I will keeping digging.  The " inexorable collection of negative influences " make me think this is a daunting task.

@Laura - Excellent points about type of engagement - affective and cognitive engagement are very different and so are the reasons for losing interest.  And of course - extrovert and introvert could play a role as well, although perhaps not easily explained  by the steady and sharp drop.

Laura, excellent point about types of engagement. Most of the students I worry about have neither type of engagement. The best, as one would expect have both types in one form or another to varying degrees. My observations resonate with those ideas.

The issue of introvert/extrovert is unclear, though I suspect the emotional engagement of extroverts, if positive, is buoyant and high energy, where for introverts, the emotional engagement is more 'satisfued' or 'contented' or cerebral.

Robin, if you are focussed on the emotional engagement then my response may be less useful. Now that the distinction is clear, I think I am focussed on the cognitive engagement. Though I am sure they are interactive.

Robin, my action research came about because there is no research encompassing the totality fo what I wanted to do, which was to change the belief systems of students (and teachers) about schooling because the prior evidence suggested that belief systems were signifcant players in student engagement. I can find no research, for example, that looks at belief systems about schooling in relation to policies Nd procedures such as the style of reporting. I wanted to tes the idea that the style of report, had a significant impact, not just on students, but on teachers and consequently on their behaviours and language. Styles of report mean whether it is achievement eg A, B, C, D, E where C has come to mean 'pass' or, progress oriented similar to reading levels, which begin at a low level and progres through levels independant on age or grade. My article https://www.researchgate.net/publication/241696820_Philosophy_-_Bremer_Action_research_Story?ev=prf_pub Summarises the research.

Article Philosophy - Bremer Action research Story

@Mark - I think schools are set up for extroverts to succeed for the most part - social interaction with the teacher or peers is highly valued - I  sense that quiet students don't fair as well in this kind of environment.

I was referring to both affective and cognitive engagement - I think they go hand in hand and I suspect that the "friends" part of school "ups" the value or enthusiasm quotient.  Of course, my main concern is the cognitive engagement.  We could bring in video games and all sorts of entertainment devices to increase enthusiasm, but I don't think that is the direction I am advocating (smile).

You paper is most welcome - looks interesting.

The previous comments all highlight very crucial psychological and cognitive factors.  Another potential factor affecting the motivation may be a physiological one.  Motivation to me in this sense would be redefined as eagerness.  Van Cauter and Knutson (2008) highlighted the trend in both adults and children to sleeping less.  Meijer and van den Wittenboer (2004) observed that the quality of sleep influences the eagerness of a student.  In their chart, eagerness was one of the crucial factors that affected the sleep-school performance of a child (Meijer & van den Wittenboer, 2004, p. 101).  

Without the required amount of sleep (in terms of qualitative and quantitative), there is an inevitable affect on the eagerness, achievement motivation and academic perfomance for a student. (Meijer & van den Wittenboer, 2004).  

Meijer, A. M., & van den Wittenboer, G. L. H. (2004). The joint contribution of sleep, intelligence and motivation to school performance. Personality and Individual Differences, 37,  95-106. doi:10.1016/j.paid.2003.08.002

Van Cauter, E., &  Knutson, K. L. (2008). Sleep and the epidemic of obesity in children and adults.  European Society of Endocrinology, 159, S59-S66.  doi: 10.1530/EJE-08-0298

@Farheen - Interesting idea - Never even occurred to me.  So your claim is that one of the reasons students are less enthusiastic is that they are getting less sleep.  Might account for some of the variations, but probably not a drop from 95 to 37.  Still, well worth investigating. 

@ Robin, I agree that it may not be accountable for the significant difference.  However, as discussed by Van Cauter and Knutson (2008), a decrease in the duration of sleep has affected various areas of an individuals life.  Such as their health (obesity), attentiveness, and emotional factors.  They may collectively affect a students motivational level or eagerness to attend.  

Van Cauter, E., &  Knutson, K. L. (2008). Sleep and the epidemic of obesity in children and adults.  European Society of Endocrinology, 159, S59-S66.  doi: 10.1530/EJE-08-0298

what is the evidence for your question?

of the cuff, i think as a child, we are influenced from outside more, whereas in youth one has other demands from self as well, resulting in reduction in exclusive school- work engagement. I base this observation on the developmental theory of Eric Erikson 

In a study a study of attitudes towards mathematics of students across grades 6 to 9 in Shanghai, China, we found that across the grades an increasing proportion of Shanghai students reported a positive disposition towards mathematics, with a slight drop in Grade 8. This might indicate that student enthusiasm for school might vary across school subjects, as well as across different parts of the world.

http://eprints.soton.ac.uk/372516/

Dear colleagues, enthusiasm for school has dropped and so has achievement, as you can read in my paper.  But I also ask are our teachers enthusiastic to teach and are teachers forming positive relationships with our learners?  What are all the REASONS WHY STUDENTS LOSE THEIR NATURAL CURIOSITY FOR LEARNING?

Article Motivation and Achievement of Malaysian Students in Studying...

Having immersed myself in complexity theory, the study of complex systems, and the attempted practice of complex systems engineering for the past twelve years or so, I realized that kids "get" complexity from the time they are born, learning who there mother is, learning a language, and realizing that they are not in control of anything in this world. I suspected that instead of nurturing this innate ability and understanding of complexity, some elementary school systems might "beat that out of them" by teaching by rote, making them think there is only one right answer to every question, and not encouraging kids to follow their interests by asking most of the questions instead of being told to do well in standardized tests or whatever. So I started volunteering in a high school robotics club, tutoring a junior in physics, then added 3rd grade science participation, and have now gravitated to concentrating on 8th grade pre-algebra and algebra classes. My initial motivation was to see how kids are being taught these days. I have found after 3-4 years of doing this that most of the teachers in my upper-middle-class community are doing fine in the sense that kids are being encouraged to enter science and engineering someday as they start to contemplate a college or university. However, this is such limited sampling that I'm almost positive that many other school districts have plenty of teachers that never went very far in their technical pursuits in college and more or less fell into teaching as an easier path, and/or the teachers never learned much about complexity and how to educate kids in how they might cope better with our world problems as they mature. So my suspicion is that kids lose their enthusiasm for school and especially higher learning as they get older because they become bored with the educational process in which they are immersed and get too distracted by other cool things such as social networking technology and the like. This is a pretty sad situation, particularly, in the US where we pompously think we're the best in everything, when the trends clearly have been in the opposite direction compared to many other countries, especially in the quality of our education system.

Here's a pithy quip on the role of pedagogy in the decline of engagement...

"Telling a kid a secret he can find out himself is not only bad teaching, it is a crime. Have you ever observed how keen six year olds are to discover and reinvent things and how you can disappoint them if you betray some secret too early? Twelve year olds are different; they got used to imposed solutions, they ask for solutions without trying" (Hans Freudenthal, 1971, p. 424).

Freudenthal, H. (1971). Geometry between the devil and the deep sea. Educational Studies in Mathematics, 3(3/4), 413-435.

As far as I know, the decline in students'  motivation mainly occurs during secondary education. 

Rita's observations match mine. There are psychosocial perspectives as well. As students move into middle school, the become more rebellious and teachers feel greater need to constrain them less they cause havoc, hence the decreasing autonomy in middle school. I have been working to change this approach in my school. I am for exampl demonstarting the simple linguistic trick of saying 'yes' instead of 'no' when studnet ask to do something most teachers regard as wasting time or avoidance. Eg when asked if a student can get a drink of water, even though they have just come in from recess, instead of 'no' I say 'yes, after you have done .........' it changes the whole social dynamic of the room. Much more pleasant.

@Rita - Thank you for the autonomy, relatedness, and competence perspective - makes the answer to the question sound simple (smile).  And Mark's response leads into my next question - How do we change this culture of oppression (okay maybe overstated) and why is it so ingrained.  Clearly, there are some small fixes like introducing a "Yes" culture.  I imagined there are a number of examples of positive teaching cultures where you would not see the same decline in enthusiasm by grade.

I once heard an interesting possible explanation for the trend of decreased enthusiasm for school as we grow:

Picture a typical kindergarten classroom. Students are not confined to one desk, facing in one direction, being forced to pay attention to one activity for an extended period of time, and remaining quiet while doing so. They are active and moving, able to communicate with the teacher and with each other, and activities change and are more varied. Children are allowed to explore, learn by doing, and experience the lessons that are presented to them.

As we progress through school, the atmosphere becomes more and more dry and boring. We are not allowed to explore, experiment, or often, even ask questions except at a specific time. The typical classroom setting for middle and high school students goes against our very nature - which is one of wanting to learn, explore, and experiment.

We need to change the structure of our classrooms to one that allows the freedom to learn in the style that is best for each individual. That will not result in chaos,as some might suggest, but rather in enhanced interest, enthusiasm, and greater learning. 

Even with college students, the more varied the presentation, the more attention that will be paid. It's all about engagement, We have to know our class, and figure out what it will take to engage them. Meet them where they are...don't expect them to come to you.

@Bonnie - Sounds quite promising to me.  I am not clear about the various attitudes towards education in the US, but standardized testing seems to be flourishing - I wonder how open the powers that be would be to creating such a learning environment.  Turns out that many of the thin Kindergarten students like, digital natives like too  (Tapscott, 2009).  Mind you I suppose one could argue the as the content of learning changes, so does the method.

Robin, it would be interesting to see the same graph by culture eg the much lauded Finland, Hong Kong, Japan, Singapore, England etc. To test your idea further. Of course there will be many confounding factors eg are those less satisfied students in some cultures pushed sideways into a second tier system or out into work etc.

It all comes down to TWO factors.  I will sum up this very briefly:

1.  Adolescence.

2.  Misfit between teaching methods and how people learn in this life stage.

Motivation occurs when there is alignment between people's goals and what goes around in their environment.

All mammals (with a couple of exceptions) tend to stop playing at a certain age, and lose a big part а their curiosity. Or rather, they focus on reproduction and survival. Humans are biologically programmed to tune out of learning, at least out of broad learning about everything. We have the longest childhood of all species, but it is not endless. 

In a way, it seems this disinterestedness that develops in children is the forerunner of apathy toward work that many adults have. Few people find soul stimulating work.

I agree with Rita that school can become a chore for children, however, I don't think learning ever becomes a chore.

I also agree with the late John Holt that what schools do is not necessarily facilitate learning so much as dole out teaching.

Maybe our education of our children is to feed the world (job market) that we've created that does not support passion and enthusiasm. Instead, children learn at some point that they must become adults who must "earn their bread" and that by whatever soul-crushing, mind-numbing and/or health-draining means. The children may pick up on this gradually and just stop fighting the system.

Perhaps most teachers (and parents) are trying to prepare the children for the "real world."

 There's a great book by Daniel Willingham on the topic, Why Don't Students Like School? A Cognitive Scientist Answers Questions About How the Mind Works and What It Means for the Classroom. Sounds basic, but it's not really. Published in 2010. http://www.amazon.com/Why-Dont-Students-Like-School/dp/047059196X

@Mark – It would be very interesting to see if this effect appears in different countries for sure – It would test Alexander's “mammal shift in interest” speculation.

@Edgar – Not sure what you mean by adolescence being a contributing factor – the effect occurs well before adolescence. But alignment of goals is probably a big factor – The gap between school board curriculum and student interests is big and developing into a chasm I would imagine with the temptations and joys of technology.

@Iyanna – Wow – That’s interesting and a bit depressing (smile) – A forerunner to the apathy of work many adults have.  Holt’s work is simple but profound, as is John Gatto (e.g. Weapons of Mass Instruction).  My only question is, how young do children learn this largely functional and deterministic thinking – Surely not in K-8, but you never know.

@Michelle – It is a wonderful book – Willingham is quite readable and persuasive.  Not sure it would explain this kind of drop mind you and so early on, but perhaps?  

Our study chowed variation within high school by age. See

Maxwell, T.W., Thomas, A.R. & Lane, T.J. 1986.  "Student perceptions of school climate: A longitudinal case study."  Education Research and Perspectives 13, 1, 27-45.

and also

Maxwell, T.W. & Thomas, A. R. 1991.  "School climate and school culture."  The Journal of Educational Administration 29, 2, 72-82. (75%) 

I did not carefully examine if somebody already noted it, but Fullan's figure shows teachers' perceptions of childrens' enthusiasm. Which is quite different from students' actual motivation (or enthusiasm).

@Tom - Thanks for this – I wonder what has changed, if anything, in 30 years?

 @ J.D.  Yes – that is a reasonable description of what typically happens in school – So why do we keep doing it?  Perhaps student enthusiasm is not that important in terms of priorities

 @Pascal – Quite right but, correct me if I am wrong, wouldn’t teacher’s be far more optimistic than students.   In other words, I would think teacher would inflate the enthusiasm estimates.  In my studies of technology and education, for example, I have never observed students being more enthusiastic than teachers.

My point is : if you want to have a measure of students' motivation, then take an as close as possible measure of it. Obviously, this is not the case with teachers' perceptions of students' enthusiasm.

I paste below a paragraph from an article (Leroy & Bressoux) recently accepted for publication in Contemporary Educational Psychology:

"Researchers have repeatedly reported that students’ motivation gradually declines from elementary to high school. Studies that have examined motivation using longitudinal designs evidenced a particularly steep decline in intrinsic motivation across the school years (e.g. Gottfried et al., 2013; Lepper & Henderlong, 2000; Spinath & Spinath, 2005; Spinath & Steinmayr, 2012). In addition to this temporal decline, a qualitative change characterized by a shift from decreasingly autonomous types of motivation to increasingly controlled types was also observed (Harter, 1981). In other words, students’ motivation, which is strongly self-determined during the first years of schooling, becomes more and more non self-determined as students progress through school (Eccles, Lord, & Buchanan, 1996; Nishimura & Sakurai, 2013). The intensity of this general temporal decline varies between subjects, depends on the subject area (Eccles et al., 1993; Haladyna & Thomas, 1979; Wigfield et al., 1991), and is particularly striking in science and mathematics (e.g. Gottfried et al., 2001; Koballa, 1995; Middleton & Spanias, 1999; Pajares & Graham, 1999; Wigfield et al., 2006)."

@Patrick - Great reference - Could not agree with you more though - Students obviously need to be asked.  Interesting that this reference cam up - I could find very little on this topic (may be more reflective of my searching skills though - smile) - What is the title of the article - I will look for it when it does come out

I would suggest reading Daniel Willingham's book Why Don't Students Like School? (2009). A very readable and lucid description of how most instructional strategies and methods fail to account for how learning occurs. The answers are apparent - it is the shoddy design and even worse instructional methods that cause the biggest problems.

The title of the article is "Does Amotivation Matter More Than Motivation in Predicting Mathematics Learning Gains? A Longitudinal Study of Sixth-Grade Students in France"

Sorry, didn't see that someone else had already posted about Willingham's book. Suggests though that it is worth a read.

To wrap all the very interesting answers up eloquently, may I direct your attention to Sir Ken Robinson's talk 10 years ago.

Nothing, I dare say, has changed in the way of addressing non-engagement like Ken says for 250 years. Where the government, and by extension the education system, sees change radically as not viable, our students, the most precious of all earth's resources aside from water, will be continuing the drop in engagement. To engage anyone, does not 'their desire to be engaged' need to be considered? Why is it then that between K-PP children are free to 'engage' in 'play to learn' but when dropped into year 1, sitting at a desk for the next 5 hours is an expectation? Why is the teacher's choice of Curriculum the optimum choice not the child's, and all the children? Are we making it creative for the children or easier for the adults? Learning is all about curiosity. If you find the hook, they  will run with the learning. Give them porridge and dried fruit, they  will run from the opportunity. 

https://www.ted.com/talks/ken_robinson_says_schools_kill_creativity?language=en

I seem to recall that John Goodlad's research reported that the decline began to accelerate in 4th grade.  One reason is that school work becomes harder at that point and increasingly so thereafter.  Another factor, at least in the US, is that so many teachers are poorly trained.  When I was working on my secondary teaching credential, for example, my one methods class was how to teach the novel; when I got my first high school teaching job, however, I didn't teach literature.  I taught writing--or tried to.  My daughter's 4th grade teacher didn't know the difference between a possessive pronoun and an adjective.  And so on.  Another important factor, of course, is social.  In our high schools, being involved in sports is more highly valued than being studious. The same is true for being popular.  The shift in the US from community to federal control of education has further complicated matters, making it difficult to match children's education to their local values and needs, which appears to affect motivation.  Our social mandate now holds that all children should go to college and earn a degree, but not all children are interested or capable of doing so.