SCIENCE
https://kids.usa.gov/teens/play-games/science/energy-games/index.shtml
http://pbskids.org/sesame/games/ready-set-grow/
MATH
http://www.mathplayground.com/mobile_factorpairup/index.htm
http://www.mathplayground.com/area_blocks/index.htm
http://www.mathplayground.com/area_blocks/index.htm
ENGLISH
http://www.spellingtraining.com/
http://www.spellingtraining.com/