Houghton Mifflin Education Place Math-related resources that include Data Place, Brain Teasers, textbook support, math links, and projects. In My World series. Choose a grade level to see all of the matching lessons for the grade. Scott Foresman Activities Center Problem of the Day Archive is a good source of additional exercises. May be used with a group or individually.
Registration is required to play most of the games.
Ads can be distracting, but overall, this is an engaging site. Suitable for elementary school curricula. Recommended for elementary and middle school students. Internet Generation A collection of math problems based on popular children's books. Though not online activities per se, this is a great resource for supplementary activities in the elementary classroom.