The abacus is a computing device on which arithmetic calculations are performed by sliding counters (beads, pebbles, or flat discs) along rods, wires or lines. The instrument may have originated in ...

Nevertheless, the abacus is enjoying a resurgence with parents ... “This course is challenging but fun,” said Rento Sasamoto, 7, a first-grader. His mother, Reiko, 39, expects her son to ...