We had a ton of fun with a Bubble Storytime!
Books we read:
Bubble Trouble by Stephen Krensky - this is really a level 1 Early Reader, but with a small group of 10-12 kids, it works ok. It rhymes and has a young child that has some trouble with the bubble bath. It's shorter and better with small groups than Strega Nona Takes a Vacation by Tomie dePaola. Strega is more complicated and a longer story. It's good with 4-5 year-olds.
Also with a small group Bubble Bubble by Mercer Mayer is fun. It's fun to let the kids find the shapes and say the different names. Then with Pop! A book about Bubbles by Kimberly Brubaker Bradley, you get the science and real info on bubbles. If they are not magic bubbles, then they only come in one shape, by themselves - round. I use several pages, marked with a post-it to show the shapes and sizes, and the recipe for bubble solution in the back. It's not a good one to read with younger than 3 year-olds. It's too complicated and a long. But for the 4-5 year-olds, it works great. The last book I used was Bubble Bear by Maxwell Higgins. It's one of the AlphaTales from Scholastic. We talk about the letter B and it's sound "buh".