# How can I use an abacus to teach concepts to a toddler?

My 18-month old son got a $10\times10$ abacus as a Christmas present, and he enjoys it as a toy. I'm fine with him just playing with it, but I don't want to miss an opportunity to introduce mathematical concepts either. I grew up in the calculator era, so it was always just a toy for me as well (with a vague concept that it used to be used for real calculations). What's the best way to use it to demonstrate simple concepts (he's just starting to grasp counting), or is there not really a good way until he's older?

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Probably too difficult at his age.. I have a niece about 4 years old that is still learning how to count! I've tried to introduce simple arithmetic concepts but it just makes her confused. I think she already know intuitively sum and subtraction, but the names of numbers, necessary for counting, are still an obstacle. –  Diego Jan 7 '12 at 16:16
The question probably belongs on parenting.stackexchange.com –  Ahmed Masud Jan 7 '12 at 16:21
@AhmedMasud Perhaps - I'm new to SE and wasn't sure about cross-posting. I thought the folks at Math.SE would be more likely to understand the actual purpose of the abacus than folks at Parenting. –  VolcanoLotus Jan 7 '12 at 16:42
A configuration of the abacus is a physical representation of the decimal expression for an integer. For an 18 month old, knowing the number 2 would be really quite advanced. I think you should show him how to use it as a rattle or make patterns with the beads. –  Adam Jan 7 '12 at 18:22
I could not agree more with Adam... –  Mariano Suárez-Alvarez Jan 7 '12 at 20:33