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
For when they get older and start learning fractions. Learn fractions in a creative way by making these fraction flowers out of paper plates- includes a set of printable fraction circles. This makes learning math fun!