The kids will love this colorful math work for number recognition. The Elementary Math Maniac: Quick and Fun Math Practice for Little Kids. Another cute way to show number recolonization and one to one correspondence.
Use crayons to color different spots of bright colors on some paper. Color over the area with a black crayon. Cut out a shape. Use the popsicle stick to scratch out the black and reveal the colors underneath. or hang
Saw these style boards on Oriental Trading for use as geometry boards. Wondered a diy hack. Use glue on bottom circle of thumbtack to secure it from being plucked out by little fingers. Sowdering About in Seattle: Toddler Busy Boxes