Lesson VOC 33
Task: Use a hammer.
Prerequisites: ADT 3, ADT 4, COG 11, SEN 12, SEN 13
Concept: Clearly there are some safety concerns when using a hammer. Even after the student has demonstrated skill in this area, supervision should be maintained. In this lesson, a standard claw hammer is used. The weight of the hammer should be such that the student can control its movement. This aspect will be verified by successful completion of Step 3. Using pilot holes drilled by the instructor is recommended, as tree greatest potential for injury is when the nail is being started. Pilot holes should minimize this possible problem.
Behavioral Objective: When requested to "please hammer these nails into that wood" and handed four regular nails, the student will place the nail into a1/2-inch pilot hole and use a hammer to drive the nail into the wood until the head of the nail is no more than 1/4 inch above the wood to a 90% accuracy level for 20 trials.
Materials: A standard claw hammer, roofing nails, standard head nails (six-penny size recommended), soft wood (preferably white pine) samples, a marker, and a drill. (Note. The drill is for instructor use only.)
Task Analysis:
1. Make sure that the student can identify each of the items from the materials section by naming them and pointing to each one.
2. Guide the student through the process of placing a nail into a predrilled pilot hole in the wood sample.
3. Demonstrate and prompt the student to hold the hammer in a solid grip. Use motor imitation (see prerequisite COG 11) to practice moving the hammer in a gross-motor manner. Ensure that the hammer weight is light enough for the student to control.
4. Using a marker, draw a target on a piece of wood and practice with the student in using the hammer to hit the target. Continue this step until accuracy appears adequate to hit the head of a nail.
5. Modify Step 4 to using the sample created in Step 2.
6. Physically guide the student through the process of hammering the nail.
7. Reduce physical guidance, replacing it with gestural and step-by-step verbal prompts.
8. Reduce all guidance until you need only the total-task verbal prompt of "please hammer these nails into that wood" after handing the student four nails and the wood with the predrilled holes. Maintain supervision of the student to ensure safety.