Phase 2 opens — P1 frequency trees (first of two sessions on 2 Sep). Starter 5/5: A5 rearranging with the subtraction step written out, A9/A10 gradient 3 and intercept −4, R9 reverse percentage £56.25, N4 HCF 6 / LCM 36, N15 error interval 8.55 ≤ x < 8.65 with correct inequality notation. Frequency trees taught from a standing start: guided example (music exam, 80 students), last three boxes found unprompted, both probability parts right including the "one of the boys" denominator trap. Practice Q1 (car ownership) tree correct plus 7/40. Q2 and Q3 trees correct, but both part (b) answers left unsimplified (15/36, 115/200) — Q3(b) asked for simplest form, so that would have lost an A mark. Q2(b) is discounted: the widget's placeholder text accidentally showed the answer. Exit ticket (garage, 150 cars) 4/4 fully independent, every fraction simplified, including P(failed car was petrol) = 22/35 — conditional probability in all but name, unprompted on the day she met the topic. Zero blanks all session. Coaching flag: she reports the arithmetic in prose rather than writing numbers into the tree boxes as she goes, and the fill-in widget has been masking that. Frequency-tree marks are awarded for correct entries in the boxes.
P2–P3 expected and relative frequency. Open with a recurring-decimal question to close the N10 loose end. Next frequency-tree question to be drawn on paper, not typed into a widget.
| Topic | Name | Change | Evidence recorded |
|---|---|---|---|
| P1 | Gap → Developing | Taught 2 Sep from a standing start. Guided example completed unprompted; practice Q1 tree + 7/40 correct; Q2/Q3 trees correct but part (b) unsimplified. Exit ticket (garage, 150 cars) 4/4 independent, all simplified, incl. P(failed car was petrol)=22/35. Taught and tested in the same session, so developing rather than secure per the N4/N10/N15 precedent. | |
| N4 | Developing → Developing | 2 Sep starter: HCF 6 and LCM 36 of 12 and 18, correct. First independent HCF/LCM question asked since it was taught on 18 Aug. One question only, so no promotion. | |
| N15 | Developing → Developing | 2 Sep starter: error interval for 8.6 cm to 1 d.p. given as 8.55 ≤ x < 8.65 with correct inequality notation — the exact gap that cost a mark on the 19 Aug exit check. One question only, so no promotion. | |
| A5 | Secure → Secure | 2 Sep starter: made x the subject of 5x + 2y = 20, writing the subtraction step before dividing. Linear rearrangement only, so the cube-root loose end is untouched. | |
| A9-A10 | Secure → Secure | 2 Sep starter: gradient 3 and y-intercept −4 read correctly from 2y = 6x − 8, though the rearranged line y = 3x − 4 was not written down first. | |
| R9 | Secure → Secure | 2 Sep starter: £45 after a 20% reduction, original price £56.25, correct. Division line 45 ÷ 0.8 not written down. |