Educational device

Claim 1

A COMPLEMENT OF EDUCATIONAL BLOCKS, EACH BLOCK COMPRISING A RECTANGULAR SOLID OF SQUARE CROSS SECTION, AND HAVING A LENGTH CORRESPONDING TO A MULTIPLE OF THE DIMENSION OF A SIDE OF SAID CROSS SECTION, AND THE LENGTHS OF SAID BLOCKS COVERING A RANGE FROM 1 TO 10, INCLUSIVE OF SAID MULTIPLES, AND EACH CARRYING INDICIA CORRESPONDING TO SAID MULTIPLE, SAID INDICIA COMPRISING A SYMBOL ON AT LEAST ONE SIDE, AND RANGING FROM 1 TO THE VALUE REPRESENTED BY SAID SYMBOL, SAID SEQUENTIAL ARRANGEMENT RUNNING FROM RIGHT TO LEFT, IN THE DIRECTION OF INCREASING VALUES; AND A RECTANGULAR OPEN-TOP BOX HAVING SIDE WALLS, SAID COMPLEMENT OF BLOCKS IN SAID BOX, ONE DIMENSION OF SAID BOX BEING SLIGHTLY IN EXCESS OF THE LENGTH OF THE LONGEST OF THE BLOCKS, FOR FINGER CLEARANCE, AND ONE OF SAID WALLS HAVING A BEVELED INNER CORNER ON ITS TOP EDGE, THREE OF THE SIDE WALLS OF SAID BOX BEING PROVIDED WITH A COMMON GROOVE PARALLEL TO THE OUTER EDGE OF THE TOP OF SAID BOX AND THE TOP EDGE OF THE OTHER OF SAID SIDE WALLS TERMINATES IN A LINE COINCIDENT WITH THE FLOOR OF SAID GROOVE AND SAID TOP BEING SIZED FOR SLIDEABLE POSITIONING IN SAID GROOVE TO PROVIDE A ROOF FOR SAID BOX, SAID TOP BEING OF PLANIFORM CONSTRUCTION AND INCLUDING AN EXTERIORLY MOUNTED HANDLE TO SLIDE THE TOP RELATIVE TO THE SIDE WALLS.