Practical route session 7 · Redesign and begin retest

Target: Redesign and begin retest. Planning estimate: 45–60 min plus continuation as needed.

Print / prior evidence

Cool-water investigation: Redesign and Retest. Compare the original sleeve with the declared redesign. Use Commit to a Redesign questions 1–2 (full student page 14), the setup and reading-log questions on each of three Retest trial sheets (pages 10–12), and Reassess the Redesign questions 1–2 (page 17). Use the supplied retest record on page 16 only for the fallback route. Teacher setup pages 2–6 and keys on pages 12–16.

Prerequisites: preceding collected evidence or the corresponding standalone kit bridge. The Cool-water investigation operational setup must be fully checked before handling.

Demonstration / learner work / collect

Analyze all first records; state the prediction, modification and constraints. The teacher confirms safe assembly and a matched question. Assemble, record the version and perform the first fresh paired trial of the old reference and redesign.

Next decision / continuation

Collect the design log, prediction and first retest record. If the first phase is incomplete, continue it first; retain 3 fresh pairs per phase. Do not replace unknown results with fallback values.

No equipment homework or mandatory student internet access. Use the complete Cool-water investigation fallback for learners who do not handle equipment or when equipment is unsuitable; record that the fallback does not show construction or testing.