Manipulative materials and arithmetic achievement in grade 1

The use of manipulative materials and visual aids in teaching arithmetic is widely accepted by teachers and those concerned with the teaching of arithmetic. The Nationa Defense Education Act is an expression on the national level of a belief in the value of manipulative materials for instruction. While most modern arithmetic programs contain suggestions on the use of visual aids and manipulative materials, much remains to be done in evaluating the effectiveness of selected materials. Cost of materials varies considerably. One main concern of school systems is the cost of materials. Are inexpensive materials as effective as more expensive ones?