Abablocks are twenty sliding, wooden, numbered cubes on two 21" rods (ensuring that blocks will not rotate, just slide). They can be used with very young children to teach counting, skip counting to 5s, simple addition, subtraction, multiples and multiplication, division and remainders, and least common multiples. Kind of a cross between the number line and abacus, the blocks let children solve problems tactually and visually. To perform simple addition, they just "slide" the number of blocks over then look at the answer on the last block in the group. Missing addend? Slide the first group over, then see how many more would need to slide over to include the block with the sum. For subtraction, start with the number of blocks in the minuend slid over to the left, then slide the number of blocks in the subtrahend to the right. The last block remaining will have the answer. Missing subtrahend? Just slide over the number of blocks in the minuend and the number of blocks you'd need to slide back to leave the difference is the missing amount. Learning multiplication facts to 5's will be easy with sides of multiples of 2, 3, 4, and 5 painted (one multiple/color for each side of the cube). 2's are in blue, 3's in green, 4's in red, and 5's in yellow. To count by 3's, turn the abablocks to the green side. Every multiple of three will be in green (other blocks just in natural finish). How many 3s in 18? A cinch to see with this device. Just count the number of green blocks to 18. Divide 15 by 4? Go to the fours side (easier to tell groups of four here), push blocks through 15 to the left, then push groups of four to the right (and count) until there are no groups of four left. Answer: 3 groups of 4 and 3 blocks remaining. Blocks that are colored on more than one side (like 12) are common multiples of the numbers corresponding to those colors. I would describe this as a robust math manipulative; it is a handy, sturdy, no-loose-pieces teaching device for demonstrating many math operations and concepts to young children (with no choking hazard!).