Shape Capers by Cathryn Falwell is a little longer than the others, but has a nice rhythm and cadence and encourages creative shape play.
Mouse Shapes by Ellen Stoll Walsh has the mice trying to hide from the cat as usual, this time in a collection of shapes. Sometimes this works ok, sometimes it just doesn't seem to hold the kids' attention as well as shorter or rhyming books.
Go, Shapes, Go! by Denise Fleming shows how the same assortment of shapes can be arranged to form two different animals, with a funny consequence. Also introduces arcs in addition to basic shapes. This one is simple enough to work for younger kids, but engaging enough for older kids as well.
Lots of Dots by Craig Frazier only covers one shape, but is a fun read and very cheerful with all the bright colored dots. It is on the longish side, but still works with most kids, unless you're pressed for time.
Color Zoo by Lois Ehlert has different zoo animals made up of different shapes. Some people love using this book for younger kids as it has very little text and bright colors (and the similar Color Farm by the same author), but I find that several of the animals are very difficult for the kids to recognize and I don't particular care for it.
In addition to the books, we also used two action songs, one to the tune of "The Muffin Man": "Do You Know What Shape This Is?"
Do you know what shape this is, what shape this is, what shape this is?
Do you know what shape this is, that I'm holding in my hand?
Then we would hold up a large foam shape and the kids would guess the shape, then we'd ask how many sides, and what color.
The other was a "Shape Shake" version of the "Hokey Pokey", where we gave each child a shape for each hand, and then we would sing:
Put your square (rectangle, circle, triangle) in, put your square out.
Put your square in and shake it all about.
Do the shape shake and turn yourself around.
That's what it's all about.
I have also started introducing an abbreviated version of my "story song" in the beginning. From what I have observed, there hasn't been any consistent use of a welcome or an ending song/rhyme, which I would like to change. I feel these repeated routines make the transitions much smoother for the kids and adults alike, and the "story song" helps get them settled. Repeated elements also get the kids more involved because they already know them, and expect them. I know with only 20 minutes it is tempting to want to just jump in to the stories, but I really feel it is well worth it to carve out a few minutes for a beginning and ending routine.
Out of all the various books that were used, my personal favorites were Lots of Dots and Shape by Shape; they seemed the most fun and easy to read, with good flow and opportunities for the kids to interact by naming shapes, colors, objects, and acting out movements like pretending to lift a heavy weight or pop bubbles. Although I did have a couple of dinosaur experts who (correctly) pointed out that Brachiosaurus was a plant-eater and therefore did not have sharp, triangular teeth. I have to confess, that inaccuracy bothers me as well. The kids also seemed to do well with Go, Shapes, Go! For the songs, I thought the "Do You Know" seemed to work best. Surprisingly, some groups did not get into the "Shape Shake".
All 10 groups we had seemed to know their shapes (and colors) pretty well. We almost tripped them up on the oval a couple of times, but they would always realize their mistake and correct it, usually without prompting. I was surprised that at least a couple of kids actually knew "rhombus" for the diamond shape (another correctly named an octagon in Color Zoo). Behavior wise, we had quite a range, which is to be expected considering we had 10 different groups at 4 different locations, and varied ages. Some were very good, well-mannered, and engaged; while others were much more fidgety, interrupting, not sitting, messing with the decorations, etc. Nothing unexpected or terribly age-inappropriate. I hope instilling some consistency in the programming with help curtail some of it.