This is Starfall http://www.starfall.com/
Harcourt math http://www.harcourtschool.com/menus/math2004/math2004_gr1.html
NLVM http://nlvm.usu.edu/en/nav/grade_g_1.html
Fun Brain http://www.funbrain.com/
Reading is Fundamental http://www.rif.org/kids/readingplanet/gamestation.htm
K-1 Math http://www.sowashco.k12.mn.us/ro/Pages/studentlinks/math/K-1math.htm
Here are some other resources that you can't find on the internet: School Library Local Public Library