Day 10 — Unseen transfer and next teaching | Year 9 Maths · T1 W1–2

Goal/materials: independently choose coordinate tools and critique a new linear model; assessment, grid and plot. Keep assessment figures unseen until this day.

Notice, 3: Retrieve Δx, Δy → gradient, coordinate averages → midpoint, Pythagoras → distance, and fixed + rate × input → model. Show symbols, not assessment numbers.
Model, 5: Correct an unscored error: from (0,1) to (2,5), “gradient 4/2=2, not 4; the rise is 4 but the run is 2.” Also name grid units.
Together, 8: Audit a new unscored line K(h)=9+3h: starting amount 9, rate 3 per hour, K(2)=15; compare its claim “always cheapest” with absent rival data. Use response routes before independent work.
Try, 6: Learner begins unseen two-week assessment, Items 1–2 or an equivalent scheduled conference. Teacher may scribe only learner-directed steps and notes mathematical prompting separately.
Check, 3: Ask “Which assumption would you verify before using a classroom model to spend real money?” Accept: real prices/domain/fees or availability; no fictitious quote can justify a purchase. Complete remaining assessment in a separate 10–12-minute check, then select next lesson from rubric, not a single score.

Shared teaching response

If a learner treats Δy as a gradient, show two lines with the same rise but different runs. If the denominator is zero, say “undefined” and trace the vertical line; never make it zero to fit the formula. If distance becomes |Δx|+|Δy|, name that as a two-leg path and contrast straight separation. If a learner produces algebra without context, require a unit, a domain and an assumption. If the concept is secure with a supported response route, remove only the mathematical prompt, not necessary access.