When I taught Kinder I found these and they turn out SO cute! They are called Beastie Bottles. Check them out here (scroll down until you see Beastie Container):
http://www.kinderteacher.com/ValentineIdeas.htm
I moved to first grade a couple of years ago and I would do them in first BUT my old Kinder team still does them and I don't want them to do them two years in a row!

You will LOVE the results! I have gotten Barbies, lions, robots, turtles, bees, lady bugs, and MUCH more.
P.S. It's an awesome site with lots of great ideas!