Match these wooden puzzle pairs to make mastering numbers as easy as 1-2-3. Groups of objects illustrate numbers 1-20, and the puzzles are self-correcting—each ... We computed the price history for the Melissa & Doug Self-Correcting Number with Amazon price historical data. This item is manufactured by Melissa & Doug. It is sold in the category Toys & Games. Amazon have it for sale at 10.99 £. We noticed a higest price of 11.99 £ and a lowest price of 5.81 £.