Do students understand the basic characteristics of a “good” weight line?
For evidence, look at responses to the Dear Darwin Concept Cartoon.
Use these criteria as you interpret students’ critiques of the 4 weight lines:
- Are the distances between neighboring tick marks equal in length?
- Do equal lengths represent equal differences in weight?
- Does the weight line start at 0?
- Is there a place on this weight line for each of the dog biscuits?
As a next step you might provide a small set of objects and their weights. Ask students to help you create a “good” weight line.