There are always exceptions to this, but a teacher needs to understand the required material and how to help their students gain the knowledge required. Beyond that, the most important thing a teacher needs to know is how to utilize the vast amount of resources to find answers.  Finally, a teacher at all levels needs to know how to learn with and from their students.  Thank you for asking this question. I think most Systems Thinkers would respond in a similar way. I attached a few paragraphs from a book that had an impact on me when I first read it. 

The obvious answer is that a teacher should know the science he/she is teaching. To which degree (e.g. a broader understanding of school science or an academic understanding) is a question of research in the field of teachers' professional knowledge. The COACTIV research program highlighted for mathematics that teachers' content knowledge is an important prerequisite high-quality teaching and basically the more the better. One could say that it should be similar for science - but other studies show that content knowledge could even have a negative impact on pedagogical content knowledge (the "expert blind spot hypothesis").

I would say that a deeper understanding of the school science is necessary, but not necessarily the science that is taught in universities - at least not all of it. There are common topics in school science that play a minor role in the university - like geometrical optics -  but there are also topics taught in the universities that are not crucial for school science, such as more elaborated mathematical approach to electrodynamics.

A deeper understanding of school science however comprises a knowledge of the concepts that should be developed and what all the science is good for in the end.

This is a great question that I wonder about as well. I agree that pedagogical knowledge alone cannot be enough to support high quality instruction at any level. My research has currently focused on the science content knowledge a teacher should know to teach high school science, particularly chemistry. In that work my group has developed a model of teacher-specific content knowledge for science. From past philosophical and empirical work and from the studies I have done, it seems that a teacher needs to understand the science in at least three domains. First, a teacher needs to know the science they hope students will learn (we call this core content knowledge). Second, a teacher also needs to understand science in unique ways to accomplish their work (we call this specialized content knowledge). For example, when a student responds to a question I pose in class I need to know enough about the content to figure out the extent to which that student is correct or incorrect, and what the student still needs to understand. This is not necessarily knowledge that I am hoping my students will learn, but that I have to know to teach. Third, a teacher needs to understand the linkages between science concepts and topics such that he or she can coherently structure activities and lessons. We call this linked content knowledge (or, previously, progressional content knowledge). My most recent and forthcoming publications are focused on this topic. I've linked one that you may be interested in. As I mentioned at the beginning, my work has focused on high school teaching. However, I think it is relevant, perhaps with some adaptation, to elementary and middle level contexts.

Article Effects of subject-area degree and classroom experience on n...

Lack of a deep understanding of science concepts can lead to misconceptions that teachers then transmit to their students. If that happens at a very early age it is difficult to then tackle those misconceptions successfully.

Thomas,

I want to participate in the discussion to reinforce the answer of Yurgos, that is simple but essential, and I support. And I agree with Ryan that pedagogical knowledge alone cannot be enough to support high quality instruction at any level.

After about 45 years of teaching and making scientific research at the University, and accordingly from the very "partisan" point of view of a scientist, I must say that I guess that the major problem is not " how much science should a person study in order to teach it", but it is "how deep must be the understanding of science concepts" to avoid fatal misconceptions that teachers can transmit to their students. And, as Yurgos outlines, "if that happens at a very early age it is difficult to then tackle those misconceptions successfully".

Accordingly, it is not simply a matter of "quantity", but mostly a matter of "quality", and the teacher has the determinant responsability of reaching a sufficient/good knowledge of "the state of art" in the discipline he teachs.

It is too frequent to find scientific misconceptions in books, magazines and TV pseudo-scientific reportages.

Giovanni

@ Giovanni, I agree! If it comes to avoiding misconceptions we know from many studies about conceptual change how hard it is to deal with misconceptions on a school level. Of course misconceptions are important wherever learning happens, also for universities and also for the public understanding of science!

An important point in my point of view is that a more "academic" knowledge of science does not necessarily support a better understanding of the science important for schools. It is sometimes just a more mathematical expression. I know very smart physicists, some of them world-class researchers, with a highly sophisticated knowledge of physics who hold misconceptions about very basic physics. An example from the mechanics of circular motion:  A very common problem is that some seem to assume that centrifugal force and centripetal force sum up to zero which is why a object moves on a circular orbit with a constant orbital speed. The literature about misconceptions in physics is full of examples like this.

The thing is that you can hold misconceptions in physics and be a very good physicists at the same time. You do not necessarily have to have a deeper understanding of school physics. If you deal with circular motion in a quantitative way you might come to correct solutions even with the wrong qualitative understanding of the underlying science. You just equal a force like gravitation with a force you call centrifugal force and solve the equation - you do not need to know that it is actually centripetal force you are talking about.

A teacher, who needs to explain this science qualitatively cannot "back down" to a quantitative basis.

I sometimes think that there are many points where a teacher needs a different scientific knowledge than a scientist - not more or less, but different. Teachers definitely need a very detailed qualitative knowledge about the physics concepts important schools to avoid misconceptions.

Thomas, Christoph,

I understand the point of Christof but there are some opinions in his answer that I do not share.

As a general comment, just to be simple and clear, I do not believe that: 1) "you can hold misconceptions in science and be a very good scientist (do you mean teacher?) at the same time", and 2) many points exist where a teacher needs a different scientific knowledge than a scientist - not more or less, but different".

My long experience as a teacher and a scientist drove me to these simple opinions:

- the "state of art" on a discipline (i.e., the general "scientific consensus" on that discipline)  must be the same for scientists and teachers, just to void fatal misconceptions;

- teachers, with the firm support of the pedagogical sciences, must be capable, by definition, of adequating fundaments of science to the school levels of pertinence.

In conclusion, I think that good scientists can certainly be bad teachers. This is a major problem for teaching, particularly at the Universities, where you get a position mostly on the basis of you capability of doing research, and you are requested to teaching, without any teaching expertise.

Ciao

Giovanni 

I am sorry christoph,

but if someone has misconceptions then he/she cannot claim to be very good at what they do because:

either they don't realize they have developed them (lack of deep understanding)

Or They know about them and choose to do nothing about it (lack of professionalism)

I don't know which is worst. And let's not forget that they are helping to produce the next generations of scientists.

science teaching is no walk in the park by any stretch of the imagination, but it needs to be taken seriously by both teacher training courses and teachers themselves.

Yurgos, let me get this straight: that is not my point! I am a researcher in the field of science education and a physics teacher myself and I would never underestimate the knowledge a teacher needs. In contrary, my point was that you can be a great SCIENTIST and still hold misconceptions about school science topics. And this is more than just opinion, there is research about this. It is for example very well know in the research about the nature of science: very good scientists often hold misconceptions about the way scientific research works.

I differentiate between the professional knowledge scientist need and the professional knowledge teachers need.

Some research about physics content knowledge in the sense Shulman used it implies that a good understanding of the school physics is not included in the knowledge of the physics important at universities. It seems to be something that is archieved maybe not independently but definitely not just automatically! This is the reason why there are countries where teachers and scientists have different science courses. A teacher also needs content knowledge that is organized by learning progressions and misconceptions, it is not enough just to know the structure of the discipline. Being aware of common misconceptions in the topic is highly challenging and needs a lot of content knowledge, but not necessarily the same content knowledge a scientist needs. 

I believe strongly that being a good teacher takes content knowledge, pedagogical content knowledge and pedagogical knowledge just as the research about teachers' professional knowledge assumes. But the assumption that knowing physics on a university level simply includes the knowledge of the physics you need to teach in schools is questionable. It is a research questions, but it is nor trivial.

All in all, I very much agree that both a good scientist and a good teacher can never hold misconceptions about the science they need. But the question whether or not they need the same science is a question for further research.

Dear All, thank you all for your input into this question.  There is a strong and active element in teacher education that eschews content development either direct or indirect, believing that pedagogy alone os sufficient.  In Ireland, teachers in primary school almost all hold the junior high school science exam but the manner in which they learned this 'material' typically by rote learning of definitional text means that yes, avoidance of  misconceptions is difficult.  The tendency becomes a matter of avoidance of content-heavy or conceptually challenging topics.  This has in turn the effect of reducing the cognitive load of much science (over-simplification).  Thus when you compare the science taught in the UK versus Ireland - that in Ireland is much 'simpler'.  So, Christolph's point about forces is moot since a teacher who doesn't know this will avoid it.  Yes, many scientists do hold misconceptions about how science works - but what about actual content misconceptions? I agree with Giovanni's point about the quality of science instruction over quantity - refer to my point above about the kind of science the teachers have had themselves. I agree with Yurgos' point about teachers being professional about seeking to improve their content knowledge, although this can be expensive and additional incentives are needed - especially in a changing curricular perspective. Surprisingly, Xavier is correct too - for some topics, elementary science teachers may actually need a lot more science content knowledge than expected, even something like magnetism especially when electricity is conceptually similar (polarity) and one can be a metaphor for the other. Ryan is correct to say that there is a balance needed in PCK but the reality on the ground is that this is difficult to achieve. 

Sorry about my english level.

I'm teaching Science in Primary 30 years ago. I know that students believe in all you say them. Then, my knowledge about science must be perfect. Children older can decide about themself over the matter. In Primary it is impossible. The science teacher in primary must know deeply about science. This make possible two things:

- An adecuated science education

- More resources to approach science in class, and how to integrate all scientific matters in the same one task

Luck in your job

If you want more, my email is [email protected]

First, thank you Thomas for getting this interesting conversation going. It’s clear it is an issue that many of us are dealing with.

I think the point Christoph makes is very important. There are many who argue that school science is different than scientist science (e.g., Deng, 2007) and, because of that, the “science” a teacher needs to know is different than the science a scientist needs to know.

There is work done in mathematics education that explores the mathematical knowledge used for the unique work of teaching, as opposed to the work of mathematics (e.g., Ball, Thames, & Phelps, 2008). In my work, I am attempting to do the same for science. What scientific knowledge does the work of teaching entail? And how is it different or the same from what a scientist needs to know? To be clear, this is in agreement with Christoph, and disagreement with Giovanni, that a teacher needs different scientific knowledge than a scientist.

May I point out that there is an issue of practicality here as well. While we may want to say, ‘teachers should understand all of the science content a scientist knows’ or, as Jose wrote their content knowledge should be ‘perfect’—this is unrealistic. For one, there is no such thing as “what a scientist knows.” This is because it depends on the scientist. Certain scientists know far more regarding specific topics than is reasonable (or necessary) for a teacher to understand. Certainly no teacher (or scientist, for that matter) can understand the depth and breadth of what “scientists” as a whole know.

I think this issue becomes especially pronounced at the elementary level, when we (at least in the US) expect teachers to be experts on science, mathematics, reading, etc. With such limited time to prepare them for teaching, we need to better understand what (and how) teachers must understand about the content.

I agree with those who believe that the knowledge of science required to teach students does not depend on their age.  However, may I shift this conversation to the purposes of teaching?  It is the purpose that clarifies the meaning of teacher's "knowledge of science".  Some teachers, myself including, see their main goal  in developing student's thinking. To them, the difference between different age groups is merely in selecting (or excluding) certain topics and adapting the language.  I saw once in a Science textbook for 3rd grade (elementary students) "sound is waves". This is silly, because  UNDERSTANDING the concept a wave is difficult even for high school students.  So what will we gain if students memorize a new word without understanding the concept involved?  Once I asked a young student (perhaps 10-year old) ""what is electricity? He responded right away: "an energy".  "And what is magnetism? - asked I again . "An energy"-  he responded. "So what is the difference between electricity and magnetism?"- No answer. 

Are there ways to learn scientific concepts at the level of understanding them instead of memorizing new words somehow connected with "science"?  Yes, there are, and we find them in the history of science.  Why cannot our students explore nature the way scientists did, say, 200 years ago?  They approached nature empirically. Before they came up with the concept "sound is a wave" they studied propagation of sound in different media, its speed, its attenuation with distance etc. They ended up with various empirical laws and valuable practical applications. And  they defined electricity not by an abstract idea ("ä flow of electrons") but by its empirical properties.  Elementary students would learn much more in this way, for instance, by experimenting with a stretch-cord telephone or with a plastic tube electrified by a paper towel.  Observing nature and asking meaningful questions (without bothering to answer them) is a good approach to learning science, because it satisfies children's curiosity and provides challeges to stimulate their thinking.

Science teachers need a solid knowledge of science in their field, but also a very good understanding of the state of the art in other scientific fields. Hence, Biology teachers, for instance, must have a very good understanding of Geology (which interacts with biology in so many ways), Physics and Maths. It is important for teachers to be scientifically literate, in order to better understand and explain new scientific developments and be able to address their students' questions. Knowledge in bioethics, history of science and the philosophy of science is also paramount. In practical terms, I don't think anyone should be a science teacher in any level without a BsC and an MsEd, at least, and without ongoing investment in further education and professional and personal development. That's what I did.  

While I agree that the more a teacher knows the easier to teach even in elementary school, much depends on the meaning of the word "knows". Let's imagine that every new teacher has a BS in one of the sciences (for instance, physics, chemistry, or biology. Will this solve the problem?

1.I observed such teachers ( in the USA ) who could not teach, although they also went through  the School of Education. They learned how to teach while on the job and from summer courses for teachers.

2. Moreover, the knowledge they acquired at a university turned out formal. Transferring the university methods into high school (or elementary school) has never produced good results.  Thus,  these teachers had to be re-educated.  But which way?

3. Again, we come to the purpose of teaching. It is the purpose that determines proper teaching techniques. My choice was to teach for understanding. This involved constantly challenging my students and expecting them to do likewise with their students. Challenge stimulates thinking, and thinking produces questions. One of my goals was to teach my students to answer those questions on their own. This is where experiment came in, the one I called the "investigative experiment". In a while the students realized that there is another way of learning, in which one looks for answers not in books and not from the instructor.  Should this not be an ultimate goal of teaching: to prepare the learner to acquire knowledge on his/her own?

Thomas raised an issue of a considerable interest to me of  "avoidance of content-heavy or conceptually challenging topics. This has in turn the effect of reducing the cognitive load of much science (over-simplification)."  Without seeing examples I may misinterpret this phrase, so I will offer examples of my own to show what my question is about. I will limit them to elementary school.  The "lever" used to be a choice topic to begin mechanics at the low level. It is no longer in science curriculum (as far as I know, at any level), instead we've got  "energy" in elementary school.   Does  this change not mean increasing the cognitive level?  If yes, do you approve it? Another example. If a teacher discards "sound is wave" and shows students instead how to make a stretch-cord telephone, will this be an "over-simplification" which you would not approve?

This question is probably done and dusted but here is my five cents: I have a research masters degree in an applied science area and I do have an honors degree in aquaculture, plant biology and microbiology. I am also a primary school teacher. I like to teach what I call big science. I try and avoid the trivialised cookbook approach to science implemented by many teachers. I like to involve my students in the rich learning possibilities brought about by long-term experimentation. These possibilities include question generating, background research, choosing, designing and conducting the experiment. Getting into graphical literacy, scientific drawing and writing.

I can do this because I have a deep understanding of the scientific process and how scientific method works. I strongly believe that children need to appreciate different ways of thinking of which thinking scientifically is one. 

Being knowledgeable means being able to guide your students to combine primary and secondary sources of information. See: 

Magnusson, S. J., Palincsar, A. S., Hapgood, S., & Lomangino, A. (2004). How should learning be structured in inquiry-based science instruction?: investigating the interplay of 1st- and 2nd-hand investigations. In Proceedings of the 6th international Conference on Learning Sciences (Santa Monica, California, June 22 - 26, 2004). International Society of the Learning Sciences, 318-325

Teaching for understanding implies stimulating students'  thinking.  The thinking process begins with a question. Thus to make thinking habitual, students shall be encouraged asking questions.  And since we talk about teaching science, learning science begins with questions about natural phenomena.  Students sometimes perceive science as an activity associated with a laboratory.  However, the original laboratory was nature, and a number of discoveries were made by observing natural phenomena, frequently without any instruments.  Here is an example.  One year I taught  younger students (11-12 years).  It was spring, and the topic was light.  I took them outside and asked them to observe any phenomena which were, in their opinion, connected with light,  formulate questions about them and record them in their notebooks. I warned them: "Your results will be graded, according to the quantity and quality of questions. You don't have to know the answers. Copying will lead to F for all with identical questions."

The next lesson was devoted to an analysis of questions to formulate criteria of good questions.  Together with students we noted that such a question as "why paper in a notebook is white" is silly because people frequently say "white as paper". We decided that a better question about paper would have been: "why a blank paper page is white but a page covered with drawings is not white?"  We came to a conclusion that a good question involves a comparison. And a comparison is an act of thinking! This helped them to evaluate the next question: "why a shadow is similar in shape to the object?"  They noticed that this rule is not always true, for one part of a shadow can be sharp, while another part of the same shadow is hazy.  Students concluded that a better question would be : "why some shadows resemble the object while other do not?"

As to answers, I suggested that some of the questions, shadows, in particular, are within their power  of answering by additional observations and experiments, while other questions ("why is the sky blue on some days?") will have to wait until they learn more of physics.  We had 3 lessons of this type, and at the last one students had much more confidence and appreciation for this activity.  One obvious advantage of this activity, which is a variety of experimentation, is a very low cost if any.  Another is that it is easily connectable with home experiments. Finally, it prepares primary students intellectually for investigative experimentation in high school.

Thomas,

I already took part in the discussion about your very interesting question.

I note, from the last aswers, that: a fundamental decoupling is arising between  "the teaching science" (i.e. the science of teaching), on one side, and "the science teaching" (  i.e., the teaching of science), on the other side.

It is trivial for me to think that both of them are needed by a good teacher of science, i.e., an appropriated method of teaching and a firm knowledge on the state of the art in the teached discipline (the so called "big science" of Peter).

Accordingly, I appreciate the contribution of Peter, who sustain the need of a  "deep understanding of the scientific process and how scientific method works" [Provando e riprovando (trying and trying again), the scientific method of Galileo].

And I appreciate the approach of Nahum, as a good example of a method of "teaching for understanding, that implies stimulating students' thinking".

But, if the main question still is "How much science should a person study in order to teach it? (a) primary level?, (b) junior high school?", I must sustain again  that a good teacher must be well prepared in "the science of teaching" and must have a good scientific background in the teached discipline.

Another misconception arising from some answers concerns the so-called university or even academic science. Science or, better, improvement and deepening of scientific knowledge, progrades wherever curiosity-oriented researchers and insitutions (and not only universities!!) are working and studying with an appropriated scientific approach (Provando e riprovando).

And the scientific results are submitted to peer-rewiewed International Journals before being rendered accessible and being discussed within the international scientific (not acadamic!!) community as a possible step  of advancement of the scientific knowledge.

As a trivial example from my expertise in Earth Sciences, as a teacher and a scientist::

1) there is no way to teach about Plate Tectonics and Earth Interior and Dynamics, for example, without knowing fundaments of the state of art on Earth Sciences, deriving from centuries of field and laboratory researches;

2) there is no way that a good experience in pedagogy and science teaching can replace a good knwoledge of science.

Giovanni

I think  a  prospective teacher should have sound knowledge of science concepts related to the environment and applications of scientific knowledge to day to day needs.His/Her  acquired learning in main disciplines; chemistry physics biology up to  age  of 18 will give confidence ,maturity and attitude for accepting new developments in science and pedagogy to the teacher to teach science to primary students. For some period He/She should be trained in organizing teaching-learning through activity and discussion and use of different resources including ICT. For high school the person should learn science in all the three components for two more years and get training  in different pedagogical strategiges and action research.

For primary level, I think the a licenciature or degree is usually sufficient. For a junior high school, I think it is necessary experience in research as a good work end of degree or master degree.

There is one school of thought that to teach something, you do not need to have experienced it as a practitioner.  Take for example, business studies/economics taught in secondary school in Ireland.  Such a teacher does not need to ever have worked in a business context only merely to have a bachelor degree in a cognate subject.  They then need to have a postgraduate qualification in education, with minimal subject specific input . For science, is this good enough, since it implies that the scientific mindset, the experimental paradigm, 'lab sense', and science as a research-based process can be 'imbibed' just by engaging with teaching it. I really do not think that this is correct.