Two Sources on a School Start Time
A student is writing a short argument about whether a district should move high school start times from 7:30 to 8:30 a.m. She has two sources. Source A is a district newsletter reporting that after the change, 'attendance improved and tardies fell by 18 percent,' but it gives no comparison group and was written by the superintendent who proposed the change. Source B is a regional study finding that later start times were associated with more sleep on school nights, but it studied suburban districts with different bus contracts and did not measure grades. The student writes: 'Both sources prove the change raises achievement, so the district should adopt it.' Her draft is due tomorrow and she has no time to find a third source.
1. Identify what each source can and cannot support, and explain why the student's sentence overreaches.
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The sentence fails on two counts: it claims achievement gains that neither source measures, and it treats association as proof.
- Source A reports attendance and tardies-behavioral measures, not achievement. It has no comparison group, so the improvement could reflect a district-wide trend, a new attendance policy, or seasonal variation. It is also written by an interested party (the superintendent), which does not make it false but does mean it should be corroborated.
- Source B supports a link between later starts and more sleep, which is a plausible mechanism for better outcomes but not evidence of them. It studied districts unlike the student's (different bus contracts), limiting transfer, and it did not measure grades.
Together the sources support a modest, layered claim: later starts are associated with more sleep, and one district reported better attendance after a change. They do not prove achievement gains. The word 'prove' is the main problem; 'suggest' or 'are consistent with' would fit the evidence.
2. Rewrite the student's sentence as a claim the two sources can actually support, and note one limitation she should acknowledge given her deadline.
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A defensible revision:
Later start times are associated with more sleep for students, and one district that made the change reported improved attendance and an 18 percent drop in tardies. These results are promising, though they do not yet show effects on achievement.
This keeps the strongest evidence, drops 'prove,' and swaps 'raises achievement' for what was measured.
Limitation to acknowledge: the attendance figure comes from a single district and a source with a stake in the outcome, and the sleep study examined different districts. With no time for a third source, the student should say so plainly-e.g., 'the available evidence is limited and comes from one district's report plus a study of other communities'-rather than implying broader support. Naming the gap is stronger than hiding it, and it protects the argument from the charge of overclaiming.