Looking for ways to give your Lower Elementary students lots of practice with big operations using the Montessori Stamp Game? Children will practice matching number and quantity by using their classroom Stamp Game to solve the 4-digit addition, subtraction, multiplication, or division problem that's on the front of the command card (in Montessori place value colors!). The answer to the problem is represented visually on the back of the card with the Stamp Game stamps, which means elf-correction