L3 · Sorting 3-D objects by one rule

Learning goal

“I can sort 3-D objects by one rule, and I can say my rule.”

Sort — to put things into groups that go together.

Rule — the one idea you use to make the groups.

Group — a set of things that go together by the rule.

Worked example

Four objects: a cube, a sphere, a box, and a cone. My rule: sort by: all faces flat, or has a curved part. Step 1: Check each object. Cube: all flat. Sphere: curved all over. Box: all flat. Cone: it has a curved side. Step 2: Make the groups. All faces flat: the cube and the box. Has a curved part: the sphere and the cone. Step 3: Say the rule out loud: "I sorted by flat or curved." Say it plainly: the cone has a flat face too - but the rule asks if it HAS a curved part. It does, so it goes in the curved group.

Check yourself — explain it

Why does the cone go in the curved group?

Paired problem — example still visible

The rule is: has a curved part. A cylinder and a pyramid - which one goes in the group? -> The cylinder (the pyramid's faces are all flat)

Faded completion — last step is yours

"In the flat-faces group, the cube's partner from our set is the ___" -> box

Ready to practise?

8 scored questions with a 3-rung hint ladder. Mastery needs 7/8 plus both gate questions.

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