These are awesome ideas! Thanks for the app recommendations. The bugs and numbers game and inventions game were HUGE hits. I never buy apps for my I pad but my son played the first inventions game so many times after he beat it that after a few months I decided to get the second one and Felix version. After he played this he developed a big interest in gears and the way things work.

Some activities my son enjoyed starting at 3.5 were:
-Lego(he played more with it after I got the big base for it to attach pieces to)
-playdohgh( I add in plastic eyes, string, buttons, Popsicle sticks or whatever I have to make crazy alien creatures)
- play Mobil camping set
- painting the wall with water outside
-putting animal stickers on paper and adding (with markers) to the paper around stickers: cookies that the animals are eating or water that they are sitting in or a tree for them to climb. This activity can go on for so long because the ideas are endless.
-window markers!

Other apps:
Elmo abc
Elmo 123
Bugs and buttons
Reader rabbit
My amazing body
Cat in the hat books

Shows:
magic school bus
Leap frog number factory
Busy town


Books:
To be continued when I have more time:)

He just turned 4 and, Currently he is into the scooby doo mystery books that don't have stuff thus too scary but I want to come up with a list of great ones we have enjoyed up to this point. Thank again for ideas everyone!