School Start Time Debate: Weighing Two Sources
A student council is debating whether to move the school start time from 7:45 a.m. to 8:30 a.m. You are on the research committee. Source A is a survey of 120 students at your school: 68% say they feel rushed in the morning, and the average reported sleep on school nights is 6.4 hours. The survey did not compare grades, attendance, or tardiness. Source B is a summary of a nearby district that made the same change: after one year, tardiness fell 18%, and the average GPA rose from 3.02 to 3.22. The summary also notes that bus costs increased 6% and that the district changed its homework policy in the same year. The council must recommend a position and explain how strong the evidence is. A member says, 'Source B proves later starts raise grades, so we should ignore Source A.'
1. Which source provides stronger evidence for the claim that a later start improves academic performance? Use specific details from both sources.
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Source B is stronger, but it is not proof. Source B reports outcome data tied to the change: tardiness fell 18% and average GPA rose from 3.02 to 3.22 after one year. Those numbers connect the later start to school outcomes. Source A reports only how students feel and how much they sleep; it gives no grades, attendance, or comparison group. However, Source B has a serious weakness: the district also changed its homework policy in the same year. That means the GPA rise could be partly or wholly caused by the homework change rather than the start time. A careful answer should say Source B is more relevant evidence but still cannot establish cause by itself.
2. Explain the limitation of Source A and what additional data would make the council's recommendation more convincing.
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Source A relies on self-report and has no outcome measures. Feeling rushed and reporting 6.4 hours of sleep do not show that a later start would improve grades or attendance. The survey also has no baseline or comparison group, so the council cannot tell whether 6.4 hours is unusual for this school or whether the feelings changed over time. To make the recommendation more convincing, the council could collect attendance and tardiness records before and after a trial, compare a pilot group with a similar group that keeps the old time, track sleep with a short daily log, and separate the start-time change from other policy changes. Even then, the council should describe the evidence as supporting a trial, not as proof.
3. How should the council respond to the member who says Source B proves the claim? Write a reasoned response.
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The council should reject the word 'proves.' Source B shows a correlation: the later start and the outcome changes happened together. But a correlation can have other explanations, and this summary names one: the district changed its homework policy in the same year. The GPA rise could come from either change, or both. The tardiness drop is suggestive, but without a comparison district or a controlled trial, the council cannot rule out other causes. The best response is: 'Source B is the stronger evidence we have, so it supports a pilot, but it does not prove cause. We should recommend a trial with clear measures and avoid ignoring Source A, which tells us students feel rushed even if it cannot show academic effects.'