Start. Give the complete F source and Parts 1–2 in assessment/FIRST-CHECKS.md. Use the same collection routine as E: 20 minutes, preserve the first response, reveal only F's change card, then 10 minutes for Part 3. Keep the initial conditions visible during the review. Record approved time/support changes. Do not introduce the new fee or budget before the first capture.
Route 30A · Make a representation that earns its space
The learner selects a blank bar, table or equation space and completes every F part. They explain what the representation makes easier to see. Blank supports carry no ratios, totals, calculated lengths, unit prices or recommendation. Record the chosen support.
Route 30B · Explain a model in a short conference
The learner completes all F parts through a recorded mathematical conference or a scribed account. Ask only neutral prompts: “What does that quantity mean?”, “Which units belong here?” and “What changed?” Record each prompt and the learner's response. Do not supply the operation or direct the recommendation. Keep the staged first capture.
Route 30C · Test your own model
The learner completes all F parts and checks one result with a different exact calculation or representation. They identify one assumption they would test before using the model in a physical situation. The second method must test the learner's model rather than copy a staff answer. Reveal the change card after Parts 1–2 have been kept.
Close: give feedback against F's criteria and select a particular next lesson or an unused F recheck. A learner may correctly change their recommendation, explain why neither option works, or retain a decision if supported by the new quantities. Judgement follows the calculation and conditions.