Over 350 children from 30 African countries gathered in Kigali on Saturday, October 18, for the 2nd Shenmo Africa Cup Abacus Mental Math Olympiad, a fast-paced, high-energy arithmetic competition.

Ever dreamt of solving math problems in your head with the speed of a calculator? Mental math might seem challenging, but it's a skill attainable through the right tools and techniques. The abacus, an ...

FORT LEE — For 10 seconds, a series of 50 random three-digit numbers flashed on the screen. After another second, abacus master Jeonghee Lee announced she'd finished the mental addition, correctly ...