Abstract: An abacus for assisting in teaching the place value, addition (including carrying), and subtraction, (including borrowing) comprises (a) a least 2 substantially parallel bars; (b) at least 18 beads mounted and independently moveable along the axis of each of the substantially parallel bars; and (c) means for maintaining each of the substantially parallel bars in a substantially fixed position with respect to each other. Preferably, the different groups of beads located on the various parallel bars are coded with some form of indicia (such as color) to denote their respective place in the 3-member sequence (i.e., ones, tens, and hundreds) of the base 10 numbering system.

Abstract: Students practice addition, subtraction, multiplication, division, and other math operations involving real numbers while have fun playing card and dice games. The card games are played with a deck of cards comprising at least two sets of playing cards. Each playing face of each playing card of each set displays an integer within the range of ?M to M which is different from all the other integers displayed on all the other playing faces of the playing cards of the respective set. M is an integer equal to or greater than 10. The dice set comprises two numerical dice bearing positive numbers, two numerical dice bearing negative numbers, and at least one operator die bearing indicia representing a plurality of mathematical operations.