GB1050292A - - Google Patents

Abstract

1,050,292. Educational appliances. M. B. SLATER. Feb. 21, 1964, 7267/64. Heading G5G. An apparatus for teaching arithmetics comprises a plurality of sheets 22, Fig. 3, of cardboard, metal or synthetic plastic and each having a workspace 28 whose area is visibly marked into basic areas totalling a cardinal number in a consecutive series, one of the areas having number representation 42 marked on a basic area and a plurality of tiles 44 ... 48 visibly marked into said basic areas one tile 48 being of the same size and shape as the workspace 28 and the other tiles 44 ... 47 of lesser size. Each lesser size tile e.g. 47 is of such a size and shape that when put into a grouping with one other tile 44 only the tiles fill said work space completely to represent the sum. The total number of tiles for each workspace representing an odd number is equal to the number and for each workspace representing an even number exceeds the number by one. Each workspace has addition facts 33 and subtraction facts 37 reproduced on the surface of the sheet 22. The addition and subtraction operations may be carried out on auxiliary sheets 52, Fig. 7, the workspaces 55 being coloured in accordingly (Fig. 5, not shown). The auxiliary sheet 52 and the sheet 22, which is divided into the workspace 28, Fig. 7, and co-operating sheets 58, 59 embodying the respective addition and subtraction operations are detachably associated on an articulated board 25 such that e.g. the subtraction operations may be detached from board 25 by unfastening tongues and grooves 53, 54, respectively. Sheet 52 or part of the sheet 22 is pre-punched for transfer to a loose-leaf binder book 60, Fig. 8. The book 60 also contains the plurality of sheets such as 22, shown in Fig. 3, and each of sheets is associated with an envelope 61 containing the corresponding set of tiles needed for performation of the addition and subtraction operations.