Answers to these questions were arrived at operationally as the children actively manipulated the materials, and the following concepts were developed: 1 . Objects which can pick up certain materials ... (iron bars, nails, magnetite) are magnets? Solution : The children tried to pick up paper clips and iron filings and to change the direction of compass needles by ... operationally by 20 of the 24 boys. The experiments were remembered and, without prompting, were repeated by THR-9A.
|Title||:||Readings in mental retardation|