Which rules does this shape keep?
Check concrete sides and corners, then connect families by their shared rules.
Explore this lesson →10 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- Matching side ticks mean equal lengths. A small corner square means a right angle. Matching arrows mark parallel sides.
- A family contains every figure that follows its rule. A smaller family keeps the rules of its larger families.
- A square is both a rectangle and a rhombus. Our trapezoids have at least one parallel pair; some classrooms use exactly one.
Something to notice
Record actual explanations, pointing, counterexamples and assistance in the shape-family observation. Selected reasons alone are not observed explanation.
Try it. Change it. Explain it.
Open the lesson to use its pictures and controls. In How it works, connect the picture to the idea. In Play & discover, change the quantities and notice what stays the same. In Your turn, answer questions and use the explanation to check your reasoning.
You can ask for help, draw on the thinking pad, or listen to the question and answer options. Progress distinguishes independent work from work completed with help.
Let’s try it →Curriculum connection
Grade 5 · 5.G · US Common Core
This lesson is mapped to these standards. A completed activity is practice evidence, not a claim of mastery. Content is checked against the linked official standards and its mathematical models are tested.