North Carolina State Standards - Unifying Concepts

The Middle Grades chapter of North Carolina's Science Standard Course of Study describes Unifying Concepts that are expressed throughout grades 6-8. These include topics involving Systems, Evidence & Explanations, Measurement of Constancy & Change, Evolution & Equilibrium, and a topic strongly related to designing -- Form & Function.

• Systems, Order, and Organization
Getting students to see things around them as systems that are made up of interacting sub-systems with inputs, outputs and in some cases feedback is important in tech ed curricula like Stuff That Works! and Nuffield's Design & Technology. You can hear students talking about systems when they describe their Pop-Up Books in a mock trade-book convention.

• Evidence, Models, and Explanation
Using evidence to make good decisions is essential to doing Informed Designing and Fair-Test Experiments. Both require the skill of Controlling Variables, a difficult skill for students wield when they are excited about testing their next prototypes. Models can help designers make good choices and take many forms: Class Demos that students watch, computer simulations that show a system perform as you redesign it, and Drawings & Sketches. There are also different Models of Design that help students reflect on their own design practice.

• Constancy, Change, and Measurement
Newton's Laws of Motion address the notions of constancy (First Law of Motion on constant velocity) and change (Second Law of Motion on acceleration), and are the central focus of the Learning By Design's Vehicles In Motion and Model Parachute task. Taking good measurements is critical to conducting Fair-Test Experiments that support design decisions.

• Evolution and Equilibrium
Although Darwinian evolution does not show up as a theme in design tasks found in DITC, having students describe the evolution of their designs can improve wrap-up discussions and students' final reports, and can be aided by students keeping a Design Diary. Also, designers study the evolution of a single product that they are redesigning when they do the research leading up to writing a Product History.
Equilibrium is key to building any structure, like Paper Bridge, Simple Machines, Model Parachute, Model Crane or Shopping Bag. The Cardboard Chair's Key Concepts movie addresses the notion of equilibrium and balance. A working understanding of chemical equilibrium is a central to the Baking Soda challenge.

• Form and Function
Almost all designs can be analyzed for their Form and Function. In the Design Brief, the Function of the desired product is defined (e.g., a model car must be self-propelled and travel over two hills), but not its Form (designer can choose any propulsion system that will get the job done). Aesthetics is an aspect of Form, and is often a concern for tech ed teachers and students. With design tasks made for science classes (see Challenges of Physical Science), Form takes a back seat to Function.