Sides and angles tell the story
Recognize triangles, quadrilaterals, pentagons and hexagons in varied forms.
Explore this lesson →10 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- A polygon has a closed boundary of straight sides that do not cross. An angle is formed where two sides meet.
- Triangles have 3 sides and angles, quadrilaterals 4, pentagons 5 and hexagons 6. Inward corners still count.
- The sides need not all be equal. Turning or resizing a polygon preserves its defining features. A square is also a quadrilateral.
Something to notice
Invite independent drawings from spoken attributes and physical models of cubes. The point-joining tasks assess supplied guided constructions, including a projected cube's hidden edges. They do not automatically assess freehand drawings, motor skills, real-model building or verbal justification. Rotated and irregular examples deliberately avoid prototype-only recognition. Cube faces are equal in the solid even though a projection distorts their visible shapes. Software checks and standard mappings do not establish mastery.
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 2 · 2.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.