Math

Grades K-6
​http://www.mathplayground.com/common_core_state_standards_for_mathematics.html

Grades K-8
http://www.mathgames.com/standards/

Grades K-12 
https://www.khanacademy.org/

Other Math Suggestions
https://www.commonsense.org/education/blog/best-math-apps-and-websites-aligned-to-common-core-standards

K-12 Math/LA Common Core Aligned
http://powermylearning.org

 
ELA

Grades K-5 
https://www.raz-kids.com/

Grades 6-8 
https://sites.google.com/site/gameonlearning/la-middle-school-games

Grades 9-12
https://sites.google.com/site/gameonlearning/la-high-school-games