Who has given the following theory? "All children go through the same sequence of development, but at different rates. Therefore teacher must plan activities for individual children and small groups, not just for the class as a whole."

Jean Piaget, the famous Swiss psychologist, proposed the theory of cognitive development which states that children pass through the same sequence of developmental stages (sensorimotor, preoperational, concrete operational, formal operational) but at different rates. He emphasized individual differences in pace of development and the need for teachers to plan accordingly, addressing individual learners and small groups rather than the whole class uniformly.