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.
FIne Motor Activity: Spirals and other Patterns (free printable; from Stimulating Learning with Rachel) Mais
Four easy to set-up and fun activities to practice fine motor skills using LEGO bricks from children in every grade level need fine motor skill help
Everyday Fine Motor Materials P is for Paperclip. I love this as a tray activity for color matching and fine motor skills
how many cheerios can you stack in 30 seconds, etc. Use pink play dough and the pink yogurt cheerios to make this a Valentine's day school class party game