Practical session 7: Commit the redesign and start retesting

Mentor Teaching · Teacher directions · 15 October 2026

Plan and prerequisites

45–60 minutes; allow continuation and complete the first phase beforehand. Planning estimate; adjust to the class.

Accurate decimal °C/time reading; calculate change; measure 150 mL; follow the matched-pair and probe-position procedure. Carry forward the preceding session evidence. The adult must check the current complete operational guide, equipment and room/water conditions before handling. Three retained first-comparison records and the original construction version are required.

Print in this order

1. Practical redesign: commit the plan

2. Practical retest: instrument checks and trial 1

Give each independent or new-evidence file only at the stage described below. Keep answers with the teacher.

Teach and demonstrate

Compare the completed F1–F3 records before designing. Retain the original version. The redesign is compared with the original one-sheet sleeve, not the bare cup. Check the prediction, changed feature, two-sheet/30 cm tape limits, footprint/height limits and uncovered base/top/probe slot. Teacher checks safe fit and insertion depth before water use.

Learner work and evidence

Retain the learner’s plan and prediction before testing. Run R1 using a fresh matched water pair and the printed retest order: original sleeve left/A, redesigned sleeve right/B. Record all standard conditions, 0/5/10 readings, actual times and room air. Save the pre-phase instrument check and plan for session 8.

Next decision and continuation

If any F trial is unfinished, continue that phase first. Do not count a proposed redesign as physically tested. At a break, drain/clean/store dry labelled versions; retain the R1 log. The next session completes R2–R3 with fresh pairs. Never substitute the fictional retest values for missing empirical readings.

Matching complete teacher key

Use the current complete operational guide for redesign, retest reference/order, phase checks and redesign keys. Keep the later reasoning check unseen.

Open the matching complete teacher guide

Access and interpretation

Offer oral, dictated, pointing or labelled responses when they show the same intended reasoning. Keep each task’s quantities, conditions and sources available. Allow extra response paper. A supplied-data explanation does not establish actual construction or testing.