GB1140915A - A teaching aid - Google Patents

Abstract

1,140,915. Teaching aid. A. H. I. MOTT. 11 Oct., 1966 [3 Nov., 1965], No. 46480/65. Heading G5G. A teaching aid comprises a base member having a recessed slot in each side of which there is a recess adapted to receive a slide member, the base member including a display surface containing two or more areas marked with symbols, and the slide member bearing permanent spaced-apart numerals each of which can be aligned with one or other of said areas by movement of the slide member, the reverse side of the slide member being blank so that numerals can be written thereon. As illustrated the slide member includes a part 26 to which other parts 27, 34 may be connected by a magnet 31 and magnetic inserts 32 or by mechanical interengagement (not shown). When used for teaching multiplication by powers of 10 the part 26 is positioned with the 2 and 4 adjacent t (tens) and u (units) in slot 25, movement to the left and addition of part 27 or 34 signifies multiplication by 10 or 100. Division is effected in the reverse manner. When using decimals a display strip showing indicia representing thousandths, hundredths, tenths, units, tens &c. is positioned in channel 25 and the slide member is provided with an aperture between each numeral and a coloured patch (17) (Fig. 1, not shown) is so positioned on the base that when viewed through an aperture it represents the decimal point. The aid is preferably made of plastics, and the reverse side of the slide member is preferably black so that it may be marked with chalk.