Marble Races with a cheap pool noodle (occupies the kids for hours.) Did this, but instead of cutting the pool noodle, the marble is small enough to fit inside the full noodle to roll down. Then can use the noodle for other things too!
We would read the book The Very Hungry Caterpillar by Eric Carle. After reading the story we would each create our own caterpillar craft. Along with this craft the class would learn and discuss the life cycle of a caterpillar.