Needless to say, given Pk's name, P was a BIG deal for us. We had a lot of fun with this one (which I have noticed that I say about many of the letters.
There was p for parade (a perennial favourite around here).
Of course, there's p for park...
My personal favourite idea (which got a bit of a lukewarm reception as Pk wouldn't accept that a picnic could be held indoors - I know, I'm not tough enough but I wasn't going to do a picnic outdoors in February) - the pizza picnic. As you can probably see from LB's stuffed face, he liked the pizza just fine.