J.C.
Mine still does this at 2 yrs, it's tough. I have to say though having my daughter go to parks and playdates has improved her clinginess. The other thought is that he's bored. It doesn't mean that you have to play to his toon so to speak, just peak his independence...have play stations in the house or his room, blocks in one spot, books in the other, cars...try coloring or painting...I go upstair specifically when I see she is getting restless downstairs. I do laundry and clean while she plays in her room. (most of her toys are there as well) Also, when she is watching tv or a video I try to chime in when I notice something. It reforces things, like abc's or whatever. I try to get her out to play once a day, but it doesn't always happen. When that happens she is very whiny.
Anyway hope this is helpful. Jen