Prerequisite bridge, model and guided practice
Read before evaluating a comparison
Target: Decide whether a comparison isolates sleeve performance. Prerequisites: read units/time, distinguish starts and changes, subtract whole numbers. If needed use Read Temperature Data Before Explaining It or the support below: 10→14°C is 4°C warming; 30→26°C is 4°C cooling.
First name the question. To compare complete sleeve designs, keep other relevant conditions matched. To investigate a single sleeve feature, vary that feature while keeping the rest of the sleeve design matched too. A confound is another relevant difference that prevents assigning the result to the intended factor alone.
Imagined setup cards for a paper comparison of complete sleeve designs. No results supplied.
Planned comparison conditions
Constructed teaching data: these values were invented for this activity, not collected in an experiment.
Condition | Sleeve A | Sleeve B |
|---|---|---|
Water mass | 100 g | 100 g |
Start | 10°C | 10°C |
Cup and lid | Cup C + lid L | Cup C + lid L |
Time / room | 20 min / 22°C | 20 min / 22°C |
Reading method | Same method | Same method |
1. What is being compared? What would be measured? Name two conditions kept the same.
2. Would changing both the sleeve and water mass still isolate sleeve performance? Explain.
Two things changed
Room 22°C, same 15-minute exposure, matching cups/lids and thermometer procedure. Two complete sleeve designs; water masses and starts differ.
A flawed sleeve comparison
Constructed teaching data: these values were invented for this activity, not collected in an experiment.
Setup | Water mass (g) | Start (°C) | After 15 min (°C) |
|---|---|---|---|
Sleeve A | 100 | 8 | 14 |
Sleeve B | 200 | 10 | 13 |
1. Find both temperature changes. Can the difference be assigned to the sleeve alone? Explain.
2. Name the confounds. Propose actual matching conditions for a better sleeve comparison.
3. What descriptive conclusion is still possible? Does comparing changes repair the confounds?
Guided practice · Repair setup cards
Paper plans, not collected readings. The question asks which complete sleeve better limits warming.
Two proposed setups
Constructed teaching data: these values were invented for this activity, not collected in an experiment.
Condition | Sleeve C | Sleeve D |
|---|---|---|
Water mass / start | 100 g / 10°C | 100 g / 10°C |
Cup | Cup C | Cup D |
Lid | Lid L | No lid |
Time / room | 20 min / 22°C | 20 min / 22°C |
Reading method | Same method | Same method |
1. Identify what differs besides sleeve design. Explain why that matters.
2. Rewrite D’s setup to match C’s relevant conditions while still comparing sleeves C and D.
3. Give a consistent measurement and recording plan, including repeated trials. If the question were about one sleeve material, what else would need matching?