Maybe you should take a look to the “health determinants perspective”. Just start by reading the following page and then you can start looking for some papers that fit better with what you are looking for in your research. Then it depends also in your perspective, of course.

Ciao!

http://www.who.int/hia/evidence/doh/en/

You can identify socio-environmental factors affecting health based on your definition of socio-environmental factors and schooling children.

The following are just examples of defining your variables. Social environment refers to physical and social setting in which the school age children live. Schooling children refers to children from age 6 to 12. From this definition you can list the socio-environmental factors affecting school age children.

Map your concepts from general to specific. Therefore you will describe physical environment and social environment.   Specifically social environment includes social organization, communication and language, education, religion, gender, customs and traditions, economy, politics, and government.

The physical environment includes geographical location, air, water, shelter, roads, access to various health-related resources, pollutants or contaminants resulting from industrialization. biodiversity, environmental epidemiology, and climate change. 

Your dependent variable is school age children and your independent variable is socio-environmental factors. Search for related and relevant literature on social environment affecting the health of school age children and provide the relationship of your variables. 

You can use these six  (6) questions in searching for related and relevant literature. (1) How do geographical location, air, water, shelter, roads, access to various health-related resources, pollutants or contaminants resulting from industrialization. biodiversity, environmental epidemiology, and climate change affect the health of school age children? (2) How do social organization, communication and language, education, religion, gender, customs and traditions, economy, politics, and government affect the health of school age children? (3) What are the effects of socio-environmental factors on the physical, mental, psychological, emotional, socio-cultural and spiritual components of growth and development among school age children? (4) What are the common health problems among school age children resulting from socio-environmental factors? (5) What is the level of awareness on the effects of socio-environmental factors on the health of school age children? (6) What are the interventions or programs implemented to address socio-environment health related problems?

You will have to include several questions on parental background and behaviors as well.

You can also look at access to water and sanitation  in school and at home, their socialization process and health seeking behaviour

I have some experiences in studies on SES and health in children in China. We found that parents' education and family income are important determinants of health status of the offspring.

A look at the 'Social Determinants of Health' as per according to WHO can be helpful. You may wish to contact [email protected] for further extraporation. 

Among the physical determinants do not forget the sound environment of children in the school, at home and in the community, where the child lives

doi:10.1016/S0140-6736(05)66660-3

doi: 10.1093/aje/kwj001

http://dx.doi.org/10.1121/1.1340642

doi:10.1136/oem.59.6.380

doi: 10.1177/0013916503256260

http://dx.doi.org/10.1121/1.4807808

doi:10.1016/j.envres.2015.08.003

http://link.springer.com/article/10.1007/s11524-013-9843-6

doi:10.1016/j.envint.2011.03.017

doi:10.1136/oem.2006.026831

School-aged children are special group who are vulnerable to disease. They are under the effect of three groups of conditions:

1. The family conditions with all health and behavioural determinants which affect the child. Family structure, parents education, parents income, ethnicity....etc are just examples 

2. School environment: with its physical and social dimensions. 

3. Learning pressure. The child is under unique pressure to learn and accommodate with the class-mate competition and influence.

In at least one study, we found 10% of school children having vision problems, most of these were uncorrected. Class overcrowding with all risks of infection and troubled learning. The physical condition of many schools was not compatible with standards to make the child in a comfortable state and weaken their affiliation to the educational system

THese are few points which might be of value