📚 Part 1: WALT, Success Criteria & Multiple Choice

WALT: Identify and classify triangles by their sides (equilateral, isosceles, scalene) and by their angles (acute, right, obtuse).

Success criteria: I can name a triangle type by looking at its side lengths or angle measures and use the right vocabulary.

Dyslexia-friendly note: Read questions aloud if needed, use a ruler to follow lines and highlight key numbers.

1. Which triangle is equilateral?

A: sides 5 cm, 5 cm, 5 cm

B: sides 4 cm, 5 cm, 6 cm

C: sides 6 cm, 6 cm, 8 cm

2. Which triangle is a right triangle?

A: angles 30°, 60°, 90°

B: angles 50°, 60°, 70°

C: angles 100°, 40°, 40°

3. Which triangle is isosceles?

A: sides 7 cm, 7 cm, 10 cm

B: sides 5 cm, 6 cm, 7 cm

C: sides 8 cm, 9 cm, 8 cm

4. Check all that apply: Which statements describe an obtuse triangle?

It has one angle greater than 90°

All angles are less than 90°

It can be scalene

It must have two equal sides

✏️ Part 2: Short Answers & Matching

5. Classify this triangle by angles: angles are 40°, 60°, 80°. Type the angle classification below.

6. Draw: Sketch a triangle that is both right-angled and isosceles (label the right angle).

7. Team challenge (brief): A compound shape is split by a diagonal into two triangles. One triangle has angles 50°, 60°, 70°. The other has angles 30°, 60°, 90°. For each triangle write its angle type and whether it could be isosceles/equilateral/scalene.

8. Match each term (left) with the correct definition (right). Draw lines between columns.

A. Equilateral

B. Isosceles

C. Scalene

D. Right

E. Obtuse

F. Acute

1. All angles less than 90°

2. Two equal sides

3. One angle exactly 90°

4. Three unequal sides

5. All sides equal

6. One angle greater than 90°

🏆 Part 3: Extension & Exit Ticket

9. Extension challenge (for advanced learners): Explain in 1–2 sentences why triangles provide stability in bridges or roof trusses. Use geometric vocabulary.

10. Exit ticket — reflection

One thing I learned today:

One question I still have:

Differentiation: Offer tactile triangle models, labelled glossary, sentence starters, or a peer buddy for learners who need support. Extension: Ask advanced learners to find and classify triangles formed by diagonals in a polygon.