General nutrition:
http://kidshealth.org/kid/word/n/word_nutrition.html
http://www.cdc.gov/bam/nutrition/index.html
http://www.hsph.harvard.edu/nutritionsource/healthy-eating-plate/
http://school.eb.com/levels/middle/article/274373
http://kidshealth.org/teen/food_fitness/fitness_nutrition_center.html#cat20130
Proteins:
http://kidshealth.org/kid/nutrition/food/protein.html
http://www.dummies.com/how-to/content/the-basic-structure-of-proteins.html
Fats (lipids):
http://kidshealth.org/kid/nutrition/food/fat.html
http://healthyeating.sfgate.com/three-elements-fatty-acids-composed-of-1717.html
Carbohydrates:
http://kidshealth.org/kid/nutrition/food/carb.html
http://www.dummies.com/how-to/content/examining-carbohydrates-energypacked-compounds.html
http://healthyeating.sfgate.com/three-elements-carbohydrates-including-sugar-8845.html
Vitamins/Minerals:
http://kidshealth.org/kid/nutrition/food/vitamin.html
http://kidshealth.org/kid/nutrition/food/minerals.html
Calories in nutrient molecules:
http://www.dummies.com/how-to/content/relating-calories-to-nutrients-in-the-food-you-eat.html
Find passwords on Edline in upper right hand column.