An easy to create activity for use with a smartboard. I like the Guess the Wordle of the Day concept, I like that students try to guess based on contextual clues, and I like that it uses the Smartboard (although it's a relatively low level usage, it's still interactive.)
Modumath as linked from Wisconsin Online learning resources. Interesting videos of algebra concepts, not a huge library but well worth the exploration. You must join http://www.wisc-online.com/ to gain access, but it's free and very interesting.