Children next examine the constructions they have made. They investigate some of the patterns that connect form and function. These patterns involve the different uses of fasteners, which determine whether or not the constructions have moving parts.If they do, they are mechanisms!
Focusing on structures vs. mechanisms:
Begin by having children describe what they have made. Select some constructions that have moving parts and some that don’t. Demonstrate the difference, by holding the base of each one, and trying to make other parts move. The base is usually the largest piece. It’s the piece you hold steady while trying to make the other parts move over it. Anything with moving parts is called a mechanism, while anything that can move only as a whole is called a structure. Write these two words on chart paper.
Help students sort their constructions into the two main categories, mechanisms and structures.
Using words and pictures, show what happens when you try to move parts of what you made.
What do fasteners do?
Focus students’ attention on how they used fasteners. Use examples of their work to show three basic ways:
What makes something a mechanism or a structure?
Using the discussion about fasteners, return students’ attention to the categories of mechanisms and structures. Demonstrate one of each, and have students identify the Type B fasteners in each one. Then ask them to look at their own constructions:
Students should discover that a mechanism uses at most one fixed fastener to attach a piece to the base, while a structure uses two or more fixed fasteners to attach a piece to the base.
Show students a simple mechanism made with Mech-a-Blocks:
Show students a simple structure made with Mech-a-Blocks:
* How could I turn it into a mechanism?