I don't think my Pagan group is doing anything for Ostara as a group. Many are part of the CUUPs in the town I live in and will celebrate there - others are pretty solitary (except for this group) and will do their own thing.
I plan to plant a few seeds indoors and color and blow eggs for ornaments! My grandfather made what we call the "googoo" tree. It is really a system of hardy roots turned upsidedown, mounted on another piece of wood, and covered with a finish. Right now we have fake plastic or wood eggs on the tree for Spring, but I think it would be special to make real blown eggs! Maybe try my hand at the Ukrainian Pysanky!