Why Sleep Matters: Sharper Minds and Healthier Teens

We’re always looking for ways to support our scholars’ academic growth and overall well-being. A recent study has shed new light on an often-overlooked factor in learning success: sleep.

Early Bedtimes, Stronger Brains

Researchers from the University of Cambridge and Fudan University studied more than 3,000 teenagers to find out just how important sleep is for cognitive development. Their findings were eye-opening! Teens who went to bed earlier and slept longer scored better on tests focused on reading, vocabulary, problem-solving, and more.

Even small differences in sleep made a noticeable impact. Those who had healthier sleep patterns not only performed better academically but also showed larger brain volumes and stronger brain function in scans.

What the Study Found

The study grouped participants into three sleep patterns:

Group One: Latest bedtimes, earliest wake-up times – averaging just over 7 hours of sleep.
Group Two: Slightly earlier bedtimes – around 7 hours and 21 minutes of sleep.
Group Three: Earliest bedtimes, longest sleep durations, and lowest sleeping heart rates – about 7 hours and 25 minutes of sleep.

While none of the groups met the recommended 8–10 hours of sleep per night for teens, those who prioritised earlier bedtimes still outperformed their peers.

Why Does Sleep Matter So Much?

According to Professor Barbara Sahakian, one of the study’s authors, sleep is when our brains consolidate memories and support development—something that’s especially critical for growing teens. Even small improvements in sleep routines can lead to noticeable long-term benefits.

At SPARK Blue Downs High, Principal Siyabonga Manana sees the effects of sleep habits in real time. “Scholars averaging fewer than eight hours of sleep often struggle with sustained attention, memory recall, and problem-solving,” he says. “It shows up in everything from academic focus to mood, and even attendance.”

Chronic sleep deprivation, he adds, can lead to irritability, stress, and even physical symptoms that send scholars to the sickbay. “We’re also seeing how late-night screen time affects their ability to wind down—tired scholars are more likely to arrive late or miss key lessons.”

How Can Scholars Improve Their Sleep?

Better sleep doesn’t require drastic changes. Here are some practical tips for scholars and families:

Maintain a consistent bedtime, even on weekends.
Power down screens at least an hour before lights-out. “A fully charged phone in the morning often tells us the brain has had time to reset,” says Manana.
Stay active during the day—physical movement supports better rest.
Plan healthy meals together—good nutrition during the day supports more restful sleep at night.
Ongoing parent support: “When we notice sleep-related challenges—like persistent lateness or fatigue—we work with families to co-create healthier evening routines,” Manana explains.

Manana also encourages families to set clear after-school routines, carving out time for homework, snacks, and downtime to help the brain shift between tasks. “Even small changes in evening habits can set scholars up for stronger mornings.”

“Sleeping is all about resetting the brain—restoring focus, balanced mood, and sharper memory the next day. That’s why it matters so much, especially in high school.” - Siyabonga Manana

Building Better Habits at SPARK

At SPARK Schools, we believe that a healthy learner is a successful learner. With the right habits, we can help our scholars build sharper minds, healthier bodies, and the resilience they need to thrive—both in school and beyond.

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