DD3 has been quite proficient at the computer since a little over 2-y-old. She likes starfall.com and poissonrouge.com so we do those. We've tried some different computer programs, but nothing so far has really impressed us or kept her real occupied. She likes to do some stuff with Dora on the nick jr website or some games from pbskids.org.
I'm trying to come up with ideas that don't involve the computer since I feel like she gets enough (if not too much) computer time already. I liked the sidewalk paint recipe -- thanks for the tip. And I think our library has themed kits ready to check out, so I may look into that.
Thanks to everyone for all of your ideas and suggestions. These kids are so hard to keep interested. Thankfully she has just taken coloring and drawing back up now that she feels comfortable holding a crayon in a writing position -- she used to get so frustrated that she couldn't hold the crayon correctly that she just stopped coloring and drawing altogether. Sigh!

It doesn't help that I also have DD11mo crawling around trying to get into everything, too!!