I have to plan my DS's b-day party which is the end of January. Too cold and rain potential to have outside. We live in an apartment, so can't do it at our house. I'm going to rent a small auditorium at one of the local parks, but my question is - what activities can I have? A lot of the party entertainment companies (we're in L.A.) are SO expensive. Does anyone have any ideas that would be fun for 3 year olds?