Topic Through the study of manual operation while enjoying without the excessiveness, you understand the mechanism of addition and subtraction, the chestnut rising and the chestnut going down, you offer the fundamental study teaching aid of the addition subtraction by the B ball roll in order to study.Solutions5 with two controllers 13.14 there is on left and right of the box two line calculation frameworks distributing the B ball to at a time a quantity which is intended in 16a 16b, game you study you can practice the mechanism of calculation without the excessiveness you roll and with function such as the fact that the child can presume that answering by hiding answering concealment cover with 17the left and right which you install on top of thing and the box which can insert 17b. In addition, adjusting to the study of B ball operation, while operating the card and numeric card 32 for problem on the card stand, 31 which, it raises to the edge of teaching aid itself 10 as a numerical formula understanding you study. Selective figure Figure 1
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