Take two or three hands-up answers, not open call-outs. Listen for pupils who say centre on the corner and zero on one of the lines; revoice that as centre on the vertex, zero on one ray. Five seconds of think-time before any hands go up.

Walk each example aloud, one at a time. Do not skip ahead.

• 35°: name the three steps as you point at the screen, centre on vertex, zero on ray, read where the other ray crosses. Then have the class say the routine back to you aloud; this re-anchors everyone before the harder examples.
• 145°: this is the load-bearing example. Pause on it. The widget shows the reading on screen, so the question is not what but why: ask the class why is 145 right and not 35? and listen for pupils naming the opening of the angle. Revoice the strongest answer: the angle is wider than a right angle, so the reading must be more than 90.
• 90°: name the right-angle fact, this is the only place on the protractor where the two scales agree. Then take a quick hands-up: anywhere else where they agree? Confirm: no, only at 90°.
• 178°: this is the careful-reading moment. Use the IWB pen to draw a small circle around the exact tick mark the ray lands on, so every pupil at the back can see which one we are reading. Do not lean into the board — the class needs to see it from where they are sitting.

This round is for talking it through together; pupils take turns at the board and the class agrees or corrects out loud.

Drag the ray to four angles in turn: try 60°, then 120°, then 135°, then 165°. For each one, call an individual pupil to the IWB to read the angle aloud and say which scale they used. Before the pupil at the board commits to a number, ask the class on a hands-up: acute or obtuse? That keeps the rest of the room thinking with you.

Listen for pupils picking the wrong scale on the obtuse angles. Revoice: the opening is wider than a right angle, so the answer must be more than 90. If a pupil reads 60 instead of 120, that is the inner-vs-outer slip catching them; pause and ask the class to compare the opening to a right angle before re-reading.

This round is the practice bank: each pupil measures the six angles at their seat with their own paper protractor, then the class compares readings on the board before moving on. Keep the pace brisk rather than over-explaining.

The six angles on each card are 40°, 70°, 110°, 135°, 155°, and 165°. The mix of acute and obtuse keeps pupils choosing the scale on every reading rather than slipping into autopilot.

Walk the room. Watch for two common slips: the protractor not centred on the vertex, and the zero not lined up on a ray. Pause the pupil to re-set rather than letting them read a wrong angle.

Stretch for early finishers: pupils who finish ahead can have a go at the reflex angle (over 180°) — the trick is to measure the smaller angle and subtract from 360°. Hand them the extension card to work out.