Theses are my favorite sites for supplementing & extending lessons as well as letting the kids have free computer time! These have good educational content and they're lots of fun too. Also, click on Domestic Chick Pinterest page for even more!
Feel free to email me with more recommendations!
Discovery Education - videos, games, homework help
Kids Click - the freedom to explore!
Science Kids - Fun science & technology
Wonderville - Amazingly fun science
Headventure Land - classical learning games
Lego Comic Builder - online comic interactive
Ed Heads - Activate your mind
Dave Ramsey - Kids site
PBS - Design Squad Nation
Science News - for kids
Cool Math - amusement park of fun
Exploratorium - hands on activities
Brain Pop - Watch quick teaching videos
Zoom Engineering - activities
Cyberchase - games
EGFI - dream up the future
Science - for girls
Engineering - games & puzzles
Typing - with Dance Mat
Spelling City - Customize your lists
Learn the body - interactive systems
Spanish - play & learn
USA Games - learn the states, capitals etc.
Educational videos - k-12
Classical music - eras, games & composers
Starfall - fabulous phonics