I drew these up for some things I was making for my kids (I’m sure I’ll be sharing those here too!)
I printed these, laminated them and cut them out. Then I used a little magnetic tape on the back. I’ve been using these on our magnetic dry erase board to illustrate our activities while the children work with actual unit blocks.
I hope these are useful for you! 
Enjoy!
UPDATE on 3/15/11:
I made a new set that matches Math-U-See! I hope you enjoy them!
Terrific blip! I just learned about your website and will definitely become a ordinary lurker now. Keep up the fantastic work.
I did the same thing for my kids, I looked EVERYWHERE to find a printable and no luck, so I made my own. Then several weeks later I did a search for “what color are the Math U See blocks” and I find your site, I wish I had found it earlier.
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Would it be possible to change the color, so that they matched the Math U See blocks (green units, blue tens, red hundreds). Thanks for the consideration.
I would be glad to work on that for you. I’ll put them in a new post when they are ready and link to them here for you. Do you know what color they make the thousands block if they have one? I’m not familiar with their materials. Thanks!
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