# PWR-134 — Scientific hypothesis generation: learner worksheet Release: Revision 7T · Full Tutorial Edition Estimated time: Estimated 26 min reading and worksheet pass Difficulty: Intermediate Equipment: Common household or practice equipment — Three ice cubes from the same tray that look similar in size, plus a metal plate or spoon, a wooden board and a folded dry cloth.; A waterproof tray, towel, timer and either a ruler or a piece of cardboard on which the starting outline of each cube can be drawn.; A paper table with columns for explanation, predicted result, result that would weaken the explanation, test result and remaining uncertainty. Space: Room-scale practice space Automated structural checklist: 10 of 10 structural checks present Evidence quality/context: G1; Focused research depth Automated method-quality band: Comprehensive Method-rating basis: Structure coverage, instruction/check specificity, alternative distinctness, source troubleshooting, comparison depth and whether purpose/check fields are authored rather than derived. Editorial review: Pending manual editorial sign off ## Before you begin - [ ] I read the tutorial authority and stop conditions. - [ ] I have the required equipment/space or a declared accessible alternative. ## Canonical source context A scientific hypothesis is a possible explanation that leads to observations we can check. This lesson uses similar-sized ice cubes melting on metal, wood and folded cloth. You will describe what happened without explaining it first, write four genuinely different explanations, state what each predicts, run one safe comparison and keep results that do not fit your favourite explanation. Target outcome: The learner produces at least four plausible hypotheses, distinct predictions and one benign controlled test capable of weakening at least one explanation. ### Authority and setup conditions - Work away from electricity and walking paths; contain meltwater and wipe spills immediately. - Use ordinary ice only, do not ingest test material and stop if cold contact is uncomfortable. - Define “melted” by one visible criterion before starting. ### Required or supplied materials - Three ice cubes from the same tray that look similar in size, plus a metal plate or spoon, a wooden board and a folded dry cloth. - A waterproof tray, towel, timer and either a ruler or a piece of cardboard on which the starting outline of each cube can be drawn. - A paper table with columns for explanation, predicted result, result that would weaken the explanation, test result and remaining uncertainty. ## 1. Record the observation neutrally Write what appears to differ in melt time, where, when and under which starting conditions without explaining it. Why: A neutral observation prevents the preferred story from entering the data. Success check: The statement contains measured conditions and no causal word. Accessible alternative: Complete the same research action — “Write what appears to differ in melt time, where, when and under which starting conditions without explaining it.” — using speech-to-text, text-to-speech, enlarged text, keyboard-only navigation, shorter work blocks or a support person. Preserve this declared check: “The statement contains measured conditions and no causal word.” Do not convert the research task into capability practice. Alternative relationship: Target preserving when declared check is preserved Learner notes: ________________________________________________________________________________ Completed: [ ] ## 2. Generate competing mechanisms List at least four explanations: heat transfer, contact area, cube-size difference and timing or placement error. Why: A hypothesis space reduces premature attachment to one cause. Success check: Four mechanisms differ in what produces the observation. Accessible alternative: Complete “List at least four explanations: heat transfer, contact area, cube-size difference and timing or placement error.” in shorter passes, or use keyboard input, dictation or a support person, while preserving this success check: “Four mechanisms differ in what produces the observation.” Use large timers, stable containers and an assistant for placement without changing hypotheses. Alternative relationship: Target preserving when declared check is preserved Learner notes: ________________________________________________________________________________ Completed: [ ] ## 3. Derive discriminating predictions For each hypothesis, state what extra pattern should appear if it is true and what result would weaken it. Why: Predictions make explanations testable against one another. Success check: Every row has support and weakening outcomes. Accessible alternative: Complete “For each hypothesis, state what extra pattern should appear if it is true and what result would weaken it.” in shorter passes, or use keyboard input, dictation or a support person, while preserving this success check: “Every row has support and weakening outcomes.” Use prerecorded fictional data instead of handling ice. Alternative relationship: Target preserving when declared check is preserved Learner notes: ________________________________________________________________________________ Completed: [ ] ## 4. Specify the measurement Choose the outcome, unit, observation interval, number of repeats and rule for missing or ambiguous observations before testing. Record the practical precision of the timer or size measure. Why: A vague outcome can be reinterpreted to favour any hypothesis. Success check: The plan contains a fixed measurement rule that another learner could follow without guessing. Accessible alternative: Complete the same research action — “Choose the outcome, unit, observation interval, number of repeats and rule for missing or ambiguous observations before testing. Record the practical precision of the timer or size measure.” — using speech-to-text, text-to-speech, enlarged text, keyboard-only navigation, shorter work blocks or a support person. Preserve this declared check: “The plan contains a fixed measurement rule that another learner could follow without guessing.” Do not convert the research task into capability practice. Alternative relationship: Target preserving when declared check is preserved Learner notes: ________________________________________________________________________________ Completed: [ ] ## 5. Choose one safe contrast Design a test that changes or measures one relevant factor while holding timing, cube size and room location as constant as practical. Why: A controlled contrast helps separate alternatives. Success check: The plan names changed variable, controls and residual confounds. Accessible alternative: A supported, seated, reduced-range or slower version of “Design a test that changes or measures one relevant factor while holding timing, cube size and room location as constant as practical.” is equivalent only when it keeps the same trained or measured target, declared configuration and success check: “The plan names changed variable, controls and residual confounds.” If any of those change, record it as a related alternative rather than an equivalent repetition. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## 6. Precommit and run Write predicted order and stop criteria, start all cubes together and record the declared outcome without changing the rule. Why: Precommitment limits hindsight and selective measurement. Success check: Raw times or observations remain unchanged beside the prediction. Accessible alternative: Complete the same research action — “Write predicted order and stop criteria, start all cubes together and record the declared outcome without changing the rule.” — using speech-to-text, text-to-speech, enlarged text, keyboard-only navigation, shorter work blocks or a support person. Preserve this declared check: “Raw times or observations remain unchanged beside the prediction.” Do not convert the research task into capability practice. Alternative relationship: Target preserving when declared check is preserved Learner notes: ________________________________________________________________________________ Completed: [ ] ## 7. Interpret without proof language Compare each hypothesis with the result, retain alternatives, note anomalies and design the next benign discriminating check. Why: One result can favour an explanation without proving it universally. Success check: The conclusion uses favours, weakens or unresolved and preserves discrepancies. Accessible alternative: Complete the same research action — “Compare each hypothesis with the result, retain alternatives, note anomalies and design the next benign discriminating check.” — using speech-to-text, text-to-speech, enlarged text, keyboard-only navigation, shorter work blocks or a support person. Preserve this declared check: “The conclusion uses favours, weakens or unresolved and preserves discrepancies.” Do not convert the research task into capability practice. Alternative relationship: Target preserving when declared check is preserved Learner notes: ________________________________________________________________________________ Completed: [ ] ## 8. Repeat before extending Run the same safe test again on a different day before changing the surface or outcome. Compare direction and size of the pattern and investigate any reversal. Why: A repeat can expose timing, cube-size or room-condition effects before a more elaborate story is built. Success check: Both raw runs remain visible, and extension occurs only when the predeclared pattern is sufficiently consistent for the learning question. Accessible alternative: Complete the same research action — “Run the same safe test again on a different day before changing the surface or outcome. Compare direction and size of the pattern and investigate any reversal.” — using speech-to-text, text-to-speech, enlarged text, keyboard-only navigation, shorter work blocks or a support person. Preserve this declared check: “Both raw runs remain visible, and extension occurs only when the predeclared pattern is sufficiently consistent for the learning question.” Do not convert the research task into capability practice. Alternative relationship: Target preserving when declared check is preserved Learner notes: ________________________________________________________________________________ Completed: [ ] ## Reflection What changed? ________________________________________________________________________________ What remains difficult? ________________________________________________________________________________ What will I repeat, adapt, ask for help with, or stop? ________________________________________________________________________________ --- Completion of this worksheet demonstrates tutorial participation only. It does not establish capability, qualification, safety clearance, diagnosis, treatment or independent validation.