☰ Contents · English

Unit 8: travel, gratitude and symmetry

Lessons 59–60 · 2 lessons · Susannah Reed with Kay Bentley. Guess What! Student’s Book 3 (Grade 3), Uzbekistan edition, 2022. Cambridge University Press; Ministry of Public Education of Uzbekistan, USAID
60

CLIL Math: are sea animals symmetrical?

Textbook: pp. 98–99
GoalUnderstand symmetry: are sea animals symmetrical? (line of symmetry).
New words
symmetry · simmetriyaline of symmetry · simmetriya chizig‘istarfish · dengiz yulduzicrab · qisqichbaqa
Explanation

A shape is symmetrical if we can fold it along a line into two matching halves. That line is the line of symmetry. A butterfly, a fish (seen from the front or from above) and a crab have one. A starfish has five arms and five lines of symmetry. Sentences: “A crab is symmetrical.” “A starfish has five lines of symmetry.”

Worked examples
A butterfly has one line of symmetry. Both wings match.
A starfish has five lines of symmetry.
Class activity

“Fold and check”: cut a butterfly or heart from paper and fold it in half. If both halves match, say “It’s symmetrical!” Draw the line of symmetry with a pencil.

Practice
1
How many lines of symmetry does a butterfly have?
2
How many lines of symmetry does a starfish have?
3
What does a line of symmetry do?
4
Name one symmetrical thing.