These aren’t very 3-d, but they work: I glued a piece of graph paper onto a piece of cardstock (the graph paper had 1 cm squares). I then cut the graph paper cardstock into 1X10 strips for the 10’s and 10X10 for 100’s. I know it isn’t the most glamorous, but it worked very well for us. Bonus: you can make as many as you want! (and they don’t take up much storage space!)
When I wanted to show a thousand, we counted out 10 of the 100’s and then paperclipped them together (as that was the only thing paperclipped, it was pretty obvious).
Although I have never done this, I’ve heard that some people bundle things such as toothpicks with a rubber band to represent the 1’s, 10’s and 100’s.
Another idea is to use beads: one bead is obviously 1, then string 10 beads onto a string and tie ends together like a bracelet to represent 10’s, etc. Down side: you’re going to end up needing a lot of beads…
-Tanya