GRAMMAR
https://learnenglish.britishcouncil.org/es/english-grammar
GAMES
http://learnenglishkids.britishcouncil.org/en/
ANIMALS
http://kids.nationalgeographic.com/
SCIENCE
http://www.sciencekids.co.nz/
HOW THE BODY WORKS
BRAIN AND SENSES
OPTICAL ILLUSIONS
http://kids.niehs.nih.gov/games/illusions/lots_of_illusions.htm