Ключевые слова: 3d, abacus, account, add, addition, arithmetic, background, basic, beads, black, board, calculate, calculation, chalk, chalkboard, child, class, color, colorful, concept, count, deduction, education, elementary, equipment, frame, illustration, isolated, kid, learn, math, mathematics, number, play, preschool, retro, school, simple, space, student, subtract, subtraction, sum, template, tool, toy, traditional, wood, wooden,