주산 코치

Abacus Coach is a learning app that doesn't just grade answers, but explains step-by-step the principles behind how the abacus beads work.

You practice through 48 lessons, starting with the structure of the abacus and the representation of 0 through 9, and progressing to direct addition and subtraction, pairs of 5, complements of 10, double complements, and multi-row calculations involving two digits.

Key Features

• Digital abacus moved by tapping and dragging
• 48 small-step addition and subtraction lessons
• Hints on the principles of pairs of 5, complements of 10, and double complements
• Feedback on errors regarding carrying, complements, digits, and calculation direction
• Sequential learning based on 90% accuracy and no hints
• Free abacus and number placement challenges
• Introduction to Hosan, where you calculate by listening to voice prompts

Master accurate movements before speed, and naturally transition to using a physical abacus and abacus-style mental arithmetic.