This board has lots of ideas for decomposing numbers in Kindergarten and First Grade!
I call this my "Math Machine!" In the past, I've used it to teach decomposing numbers. So if there are only four "beads" on the rope, we would move them around and find all of the different ways to make four, such as 3 + 1, which is what is shown in the photo now. Check the link to learn more.