Final answer:
Middle school students have well-developed grasp patterns for objects, but patterns involving tools may continue to mature. Imitation plays a role in passing along tool making skills and the development of language.
Step-by-step explanation:
The overall grasp patterns for a variety of objects are well developed by middle school students, but those involving tools may continue to mature into the early school years. The ability to imitate plays an important role in passing along the complex skills of tool making. The theory suggests that tool making and language may have evolved together over time.