Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown.
Level 1 · Warm-up
1 Sleep is best described as…
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The second half of learning — consolidation moves memories into permanent storage.
2 How long can ONE all-nighter disrupt memory consolidation?
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Up to 48 hours, so it also weakens the next two days of learning.
Level 2 · Core
3 Daily 30-minute study across a week gives your brain how many consolidation cycles?
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7 — one per night. Cramming the same hours into one session gives just one rushed cycle.
4 It is 10pm before an exam and one topic is unrevised. What does the lesson recommend?
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Sleep. 7 hours + 1 hour study beats 5 hours + 3 — the lost consolidation costs more than the extra hour gains.
Level 3 · Challenge
5 Why is caffeine after about 2pm a study problem, not just a sleep problem?
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A late dose is still active at bedtime, degrading sleep — and degraded sleep fails to file the day you just studied.
6 A student can recite definitions perfectly but cannot apply them to unfamiliar problems, and has been sleeping 5 hours. Which sleep stage were they losing most?
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REM — it dominates late in the night and does the connecting work that application requires. Facts survived; the connections did not.