While we haven't started a formal math curriculum yet, I have been trying to periodically use Cuisenaire Rods. Since we're still in the exploration/familiarization stage with the rods (and probably will be for months, until he's ready for more), template matching activities seem to work well for us. He enjoys them and they let us have conversations about the rods and how they compare to one another. He also enjoyed the element of counting up each color of rod at the end. Since it is almost his third birthday, I made some birthday templates for him.
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