Toddler threading activity with giant cardboard beads. Could be a little project to have them paint the tubes, let them dry, and cut the tubes into smaller lengths (with some help). Add stickers for decoration and even more fine motor practice!
Graeme likes the cupcake train idea. Two very easy alternatives for creating a train cake your kids will love. One is a Thomas the Train cake in the shape of their birthday number, and the other is a cupcake train.