Labor (2) Teaching--Aids and devices (2) Teaching (2) Mathematics (2) Evaluation (2) Education, Primary (2) Concepts (2) Evaluación (2) Material didáctico (2) Conceptos (2) Enseñanza (2) Trabajo (2) Enseñanza primaria (2) Matemáticas (2) Wealth (1) Teachers (1) Teacher-student relationships (1) Students (1) Research (1) Play (1) Methodology (1) Mathematicians (1) Learning, Psychology of (1) Language and languages (1) Interviews (1) Fractions (1) Families (1) Education (1) Dressmaking (1) Design (1)