Common Core math games
Math Playground has videos on subjects the students can watch for Math instruction. Some of the games are for practice, but many of the games create a deeper understanding of math concepts. I think the site promotes the kind of thinking that is expected with the new common core standards.
How I Use It
I have the students watch a video on a mathematical concept, and then they can create their own videos using a different program. Additionally, I use it for fast finishers to play math games to deeper their understanding of a concept. The students love the games where they can compete against other students in our room.