I think you could also have multiple pipe cleaners coming from one number and students have to show multiple ways to add numbers to get to that number. Counting with pipe cleaners and beads. Great for fine motor development too.
Number sense - use magnetic numbers to fill in missing numbers
Simple to set up Maths Centre activity for home or the classroom to teach doubling ideal for use with Foundation Stage or Kindergarten.
Feed the Hungry Shape Monsters Sorting Game - The Imagination Tree
Pinecones & Elastic Bands Fine Motor Activity (from The Imagination Tree)