Sleep, Food and Screens in Exam Term: What Actually Moves Marks

Every September, Kenyan households prepare for assessment season by doing more: more revision hours, more tuition, more pressure, later nights. And every year a proportion of capable, well-prepared learners walk into the exam hall exhausted, hungry and running on four hours of sleep, and produce a paper that does not reflect what they know.

This article is about the three things that determine whether a learner can actually use what they have revised: sleep, food and screens. It is deliberately practical. Information current as of Term 3, 2026, with KPSEA on 26 to 28 October and KJSEA from 26 October to 20 November.

Sleep is part of revision, not a break from it

This is the fact most families have backwards. Memory is not stored at the moment of learning. It is consolidated afterwards, and much of that consolidation happens during sleep. A learner who revises Integrated Science until 11pm and then sleeps five hours has done the first half of the job and skipped the second.

The practical consequence is stark. Cutting sleep to add revision hours is not a trade of rest for work. It is a trade of stored knowledge for unstored knowledge. The extra hour at midnight is spent on material that will be partly lost because the process that would have kept it was cut short.

Most Kenyan candidates in exam term are getting six hours or fewer. If your Grade 9 learner is in bed at 11.30pm and up at 5.30am for a long commute, they are running a two to four hour daily deficit through the most important eight weeks of their schooling so far, and it compounds. By week three of a deficit like that, attention, recall and mood are all measurably worse.

What the deficit actually costs

The bottom bar deserves attention. Careless errors, the marks lost to misreading a question or dropping a sign, rise sharply with tiredness. A tired learner does not just know less. They make more mistakes with what they do know, and those are the marks parents find hardest to understand afterwards, because the child could clearly do the question.

Food: the exam is sat by a brain that needs fuel

The brain runs almost entirely on glucose from what has recently been eaten. A learner who sits a 9am paper after a cup of tea and nothing else is sitting it with a working memory that starts fading around the second question of the second paper. On KPSEA Day 1, that second paper is English, sat straight after Mathematics.

Breakfast on an assessment morning should be slow-release and familiar. Uji, porridge, bread with eggs, sweet potato, bananas, groundnuts. Slow release matters because sugary food and drink produce a spike and then a slump about an hour later, which lands mid-paper. Familiar matters because an assessment morning is not the day to introduce anything the stomach has not met before.

Water is the quiet one. A learner who drinks little through a hot October day and then sits a two-hour paper is mildly dehydrated by the second hour, and mild dehydration produces headache, fatigue and worse attention. A bottle of water in the bag and permission to drink it is one of the cheapest exam interventions that exists.

Screens: the damage happens after lights out

Most households believe the child is asleep at 10pm. A great many of those children are on a phone under the blanket until midnight or later, and the parents find out only when a teacher mentions the child sleeping in class.

The phone does two separate kinds of harm in exam term. The first is the obvious one: time. An hour of scrolling is an hour not slept. The second is less obvious and more damaging: the light and the stimulation delay the onset of sleep itself, so a child who puts the phone down at 11pm may not actually fall asleep until close to midnight. The device cost them the hour of scrolling and another hour of lying awake afterwards.

The fix is not a lecture. It is a shelf. Phones in the household go on a shelf in the sitting room at a fixed time, an hour before bed, and stay there until morning. This includes the parents' phones, because a rule that applies only to the candidate is a punishment, and a rule that applies to everyone is a household habit. It is uncomfortable for about a week and then it is simply what the family does.

If the phone is genuinely needed for revision, and sometimes it is, the revision happens at the table before the shelf time, not in bed. A learner who says they need the phone in bed to revise is, with respect, not revising in bed.

A weekday that works during exam term

Notice that revision here is ninety minutes and sleep is eight and a half hours. Most families would reverse that ratio in October and believe they were being diligent. The evidence is unambiguous that the version above produces the better paper.

Take Brian, a Grade 9 learner in Nakuru

Brian's family did everything they had been told. From the start of September he revised until midnight, was up at 5am for the matatu, and had a tutor on Saturdays. His mother made sure the phone was in his room so he could use revision apps. His practice paper marks fell steadily through September, and each fall was met with another hour added to the evening.

His aunt, a nurse, asked one question at a family gathering: how much was he sleeping. The honest answer was about five hours, and the phone was on until well past midnight most nights. Nobody had connected the falling marks to the rising hours, because the rising hours looked like effort.

They cut revision to ninety minutes, moved bedtime to 9.30pm, and put every phone in the house on the kitchen shelf at 8.30pm. His mother reports that the first week was miserable. By the third week his practice marks had recovered past their September starting point, and he was doing less than half the revision he had been doing when they were falling.

Common mistakes to avoid

• Trading sleep for revision. It throws away the part of revision that happens while asleep.
• Tea-only breakfasts on exam mornings. The second paper is sat on an empty tank.
• Sugar before a paper. The slump arrives mid-exam.
• Believing the child is asleep because the light is off. Check where the phone is, not whether the room is dark.
• A phone rule for the candidate only. It becomes a punishment. Make it a household rule.
• Cramming the night before. The best thing to do the night before a paper is sleep nine hours.
• No water through the day. Mild dehydration costs concentration in the second hour.

Putting it alongside the revision plan

None of this replaces revision. It is what makes revision usable. Pair it with a plan that fits inside the ninety minutes above, which is what our guide to a revision timetable your child will actually follow is built around, and with the method in how to revise so it sticks, which gets far more out of a short session than rereading does.

For the final stretch specifically, the KJSEA eight-week plan and the KPSEA eight-week plan both assume a rested learner. Materials for those sessions are on the Grade 9 and Grade 6 hubs, and the study packs bundle notes with revision papers so a ninety-minute session has something specific to do. If the anxiety is what keeps your child awake rather than the phone, our article on exam anxiety covers that separately. Guidance on learner wellbeing is published by the Ministry of Education.

Frequently asked questions

Is nine hours really necessary for a Grade 9 learner?

Eight to ten is the range for that age. Nine is a sensible target in exam term. Six, which is what most candidates get, is a sustained deficit.

What if the commute makes an early night impossible?

Then cut revision rather than sleep. Ninety minutes of rested revision beats three hours of tired revision, and the early start is a fixed cost you cannot change.

My child says they cannot sleep early. What helps?

Phones out of the room an hour before bed, a consistent bedtime even at weekends, no revision in bed, and some physical movement after school. Sleep onset usually shifts within a week or two of a consistent routine.

Is coffee or an energy drink useful before a paper?

No. A sugary energy drink produces a slump mid-paper. Water and a proper breakfast do more, reliably.

Should we stop the phone completely during exam term?

Not necessarily. Out of the bedroom and on a shelf from an hour before bed is enough. Complete confiscation tends to produce a fight that costs more sleep than the phone did.

What should the night before KJSEA look like?

Light retrieval of formulae and definitions before supper, everything packed, phone on the shelf, and nine hours of sleep. Nothing new.

In summary

The learner who arrives rested, fed and hydrated has access to what they revised. The learner who arrives on five hours of sleep and a cup of tea has revised just as much and can reach less of it. In the final eight weeks before KPSEA and KJSEA, protecting sleep is not a soft option alongside the real work. It is part of the work, and it is the part most Kenyan households cut first.

Set a bedtime, put a plate in front of them in the morning, and find a shelf for the phones. It costs nothing, and it is worth more marks than the extra hour at midnight ever was.