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Lesson plan · Ages 14–18 · intermediate

Find the edge

Bracket the model’s nuclear-fusion window and reason from cases on both sides.

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Time

45–55 min

Group

Groups of 3–4

Learning objectives

Use multiple trials to identify a threshold interval rather than a single magic value.

Learning objectives

  • ✓Order trials and bracket two model boundaries.
  • ✓Explain why evidence near a threshold needs repeated, controlled cases.
  • ✓Distinguish an interval supported by tests from an exact physical constant.

Teacher preparation

  1. 01Assign each student one ε case before groups combine results.
  2. 02Ask for predictions before revealing the projected fate.
  3. 03Keep all other dials at our-universe settings.

Procedure

0–8

Set the question

Ask whether the life-permitting region has a point edge or an interval. Students mark 0.007 as the baseline.

8–25

Distributed trials

Each student opens one assigned universe, records the projected fate, ignites, and reports the result without adjusting any dial.

25–40

Build the boundary map

Order all four ε values. Shade confirmed failure, confirmed survival and the untested gaps between them.

40–55

Argue from brackets

Groups state lower and upper boundary brackets, then explain why the exact threshold is not established by four trials.

Controlled universes

2dwc4gub5fzgontdw3

ε = 0.0058

Too little nuclear binding: hydrogen remains unfused.

Expected toy-model result: hydrogen

Launch in classroom mode →

2dwd5gub5fzgontdw3

ε = 0.0062

Just inside the model window.

Expected toy-model result: success

Launch in classroom mode →

2dwf5gub5fzgontdw3

ε = 0.007 · ours

Baseline stellar fusion and observer path.

Expected toy-model result: success

Launch in classroom mode →

2dwi7gub5fzgontdw3

ε = 0.0082

Too much early fusion consumes the useful hydrogen.

Expected toy-model result: burnt

Launch in classroom mode →

Discussion questions

  1. 1.What interval contains the lower boundary? The upper boundary?
  2. 2.Which new ε values would reduce uncertainty fastest?
  3. 3.Why is a green slider band not itself evidence?

Assessment

Students report two brackets—0.0058–0.0062 and 0.007–0.0082—and explicitly avoid claiming an exact empirical threshold.