Ключевые слова: abstract, addition, background, blue, chalkboard, child, childhood, class, classroom, early education, education, elementary, exam, explaining, flat, flat lay, home, homework, kid, kids, kindergarten, knowledge, learn, logic, math, mathematic, mathematics, maths, number, one, plastic, preschool, preschooler, primary, pupil, puzzle, school, school education, sign, smart, student, study, studying, symbol, teach, text, three, two, wooden, young,