The links listed below are for kids and the young at heart.
http://kids.usa.gov/
http://www.funology.com/
http://www.funbrain.com/
http://kids.nationalgeographic.com/
http://www.nasa.gov/audience/forkids/kidsclub/flash/#.UxEAUBj2MZ8
http://www.sesamestreet.org/
http://www.sikids.com/
http://kids.albrightknox.org/loader.html
http://www.dare.org/kids/
http://www.monitoringthefuture.org/