
Angle Architect
An angle measures the amount of turn between two rays: angles range from acute through reflex, a protractor reads the inside turn from 0° to the degree, and missing angles can be found from 90°, 180°, and 360° totals.

What your child will figure out
- Classify visible angles as acute, right, obtuse, straight, or reflex by comparing their turn with 90° and 180° and noticing whether the outside turn is used.
- Measure and construct angles with a protractor by aligning the baseline, starting at 0°, and reading the correct scale.
- Estimate an angle before revealing the protractor labels, then use measured error as feedback.
- Find complementary, supplementary, and compound missing angles using 90°, 180°, and 360° totals.
The levels
- Spot the sharp roof
Recognise and reproduce a 38° acute angle.
- Find the square corner
Recognise a 90° right angle by comparison with a square corner.
- Name the wide roof
Recognise and reproduce a 124° obtuse angle without relying on arm length.
- Lay the straight beam
Recognise and reproduce the 180° half-turn made by a straight line.
- Trace the outside turn
Recognise a 235° reflex angle as the outside turn to a ray whose inside angle is 125°.
- Aim the brick lift
Measure and construct a 65° angle from the correct 0° baseline.
- Tune the skylight
Measure and construct 127° to the nearest degree.
- Estimate the roof pitch
Estimate 43° with labels and the blueprint guide hidden, then inspect the error.
- Judge the loading ramp
Estimate the obtuse angle 148° within 6° without a visible target guide.
- Complete the square frame
Find and build the 34° complement of 56° using a concealed result and a 90° total.
- Finish the straight brace
Find and build the 117° supplement of 63° using a concealed result and a 180° total.
- The twin-structure test
Prove that a concealed 133° angle completes both a 47° straight brace and a 360° hub with 90°, 72°, and 65° known.
Ready when they are.
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