The Project’s Guiding Question
How does sleep affect the way our bodies and brains work, and what does our own school’s sleep data tell us?
Project Overview
Students investigate sleep as a biological process and then run a real study on their own school.
They start by learning what happens in the body and brain during sleep. Then they design a sleep census, recruit volunteers from across the school, and collect data over several weeks. The project teams are the research team. Everyone else is a participant.
Throughout the project, students act as young biological researchers. They design the instrument, recruit the school, manage the data, analyze the results, and report back to the community that provided them with the data.
Final Product
Students produce two things.
- The School Sleep Report: A research brief presenting the census findings: the research questions, the method, the participation rate, the data, the biology behind the patterns, the limits of the study, and evidence-based recommendations for the school.
- The Results Reveal: A public event where the school gets its findings back. The people who logged their sleep see what the data showed. A study that takes data from a community and never reports back to it has failed at something important.
The report should include:
- A clear set of research questions
- The data collection instrument and how it was designed
- Participation numbers, including who joined, who dropped out, and who never joined
- Charts and visual summaries of the findings
- Biological explanations for the patterns found
- Honest discussion of what the data cannot show
- Recommendations for the school, families, and students
Learning Goals
Students will:
- Explain the biological functions of sleep, including circadian rhythms, sleep stages, and hormonal regulation
- Describe how sleep supports memory consolidation, learning, mood, immune function, and growth
- Design a research instrument that produces usable, comparable data
- Recruit and retain participants in a real study
- Manage, clean, and analyze a real dataset
- Distinguish correlation from causation
- Recognize sampling bias and non-response bias in their own results
- Apply research ethics: consent, anonymity, and the limits of what you may ask of participants
- Communicate scientific findings to the community that produced the data
- Collaborate and manage a project with real deadlines and real dependencies
The Challenge
Students are expected to think like biological researchers, and not like people who simply give advice.
Running a study on real people introduces problems a classroom experiment never does. People forget to log or join late. People answer what sounds good, instead of what is true. Every one of those problems is part of the science, and the report has to address them.
Students should understand that sleep connects systems. The brain consolidates memory. Hormones regulate growth, appetite, and stress. Light exposure sets the circadian clock. Screens, homework, sports, part-time work, and school start times all press on that biology.
When running the census, students should continually ask:
- Is our question measurable with the data we can actually collect?
- Who is missing from our sample, and why?
- What is the biological mechanism behind this pattern?
- Could something else explain what we are seeing?
- Are we reporting what we found, or what we hoped to find?
One rule shapes the entire project. Students observe sleep. They do not manipulate it. Nobody is asked to sleep less, stay up later, or change their habits for the study. Participants log their normal lives. This is not a limitation to work around. It is how human research ethics work, and understanding that boundary is part of the science.
The PBL Recipe
Ingredients
- Existing sleep studies and reliable science sources
- School-wide volunteers
- Daily sleep logs from participants
- A simple digital form and a paper backup
- Curiosity
- Critical thinking
- Data management and analysis
- Research ethics
- Persistence (because participation always drops)
Initiate
Students explore what sleep is and why every animal does it. They study sleep stages, circadian rhythms, melatonin and cortisol, and what the brain does at night.
They examine the gap between what teenagers biologically need and what teenagers actually get, and discuss the reasons behind it.
Every student in the project keeps a personal sleep log for one week. This is the pilot. They will discover firsthand that logging is annoying, that they forget, and that some questions are hard to answer honestly. This experience shapes the instrument they design in the next phase.
The phase ends with a Project Kickoff. Teams choose a research angle:
- Sleep duration and alertness during the school day
- Screens, light exposure, and sleep timing
- Weekday and weekend sleep patterns, and social jetlag
- Sleep, mood, and stress
- Sleep, sports, and physical recovery
- Sleep across grade levels and ages
Plan
This is where the census gets built and the volunteers sign up.
Design the instrument: The whole school fills in the same core log. If teams each use their own version, the data cannot be combined. The core log must take under one minute each morning:
- Time went to bed
- Estimated time fell asleep
- Time woke up
- Number of night wakings
- Sleep quality, rated 1 to 5
- Screen use in the hour before bed
- Caffeine after mid-afternoon
- Alertness in the first lesson, rated 1 to 5
Each team may add a maximum of two questions of its own. The core stays identical for everyone.
Set up the channel: One digital form with a QR code, plus a paper option for students without phones. Teams test it on twenty people and fix what breaks before going wider.
Protect anonymity: No names. Each participant creates a code they can reproduce daily without writing it down, for example the first two letters of a parent’s first name plus their own day of birth. The code links a person’s entries to each other without identifying them. Consent forms go to families before recruitment, handled by the teacher.
To be included in the analysis, a participant needs at least 7 logged nights inside the window. Late joiners are tagged as a second cohort. Comparing them to the day-one joiners is itself a finding worth reporting.
Recruit the volunteers: This is the make-or-break task of the phase. A weak recruitment means a weak dataset, and no amount of good analysis fixes that later.
Recruitment runs as a campaign, not an announcement:
- A recruitment drive: Sign-up desks at break, staffed by the project teams. QR codes and paper forms help create participant codes.
- Team pitches in classes: Ninety seconds per team - our question, why it matters, how to join.
- A myth wall: Statements about sleep posted in a corridor. Passers-by vote true or false. Teams reveal what the research says. It draws a crowd and creates a reason to talk to people.
- A reaction time station: A simple tap test. Compare your score to last night's sleep. It makes the abstract immediate and it converts curiosity into sign-ups.
- A grade participation board: Live sign-up counts by class. Competition works.
- Late-join visibility: Posters stay up through day 10. Announce the closing date early and repeat it.
One team should own recruitment and data quality for the whole census. That job is bigger than it sounds.
Each team also writes a work plan with roles, deadlines, ethical guidelines, and success criteria, including a target participation number.
Execute
Monitoring and reporting: Participants log daily for 21 days. Intake stays open for the first 10. Participation will drop - it’s natural. Planning for it is essential:
- Post a weekly data drop in the corridor: one chart, one surprising number, no analysis yet
- Recognize the class with the highest logging rate each week
- Send a mid-study reminder with a teaser finding
- Track daily response rates and act when they fall
Teams monitor the incoming data continuously. If a question is being skipped or answered strangely, they note it. That goes in the report as a method finding.
Analysis: After day 21, the data closes. Teams clean the dataset, exclude entries below the 7-night minimum, and check for impossible or duplicated responses.
They analyze their own question against the shared data, using tables, graphs, and visual summaries.
Then they connect patterns to biology. A pattern is not a finding until they can explain the mechanism or state clearly that they cannot do so.
Teams also examine their own sample. How many students participated out of how many were invited. Which grades are overrepresented. Who dropped out and when. Whether the late cohort differs from the early one. These numbers go in the report.
Deliver
The students write the School Sleep Report and prepare the Results Reveal.
The report presents the questions, method, participation numbers, findings, biology, limits, and recommendations.
Recommendations must be specific and workable. “Sleep more” is not a recommendation. A proposal about assembly timing, homework distribution before test weeks, or a screen-curfew campaign built from the data – are valid recommendations.
The event preparation is a project of its own. Teams handle:
- The running order and who presents what
- Visuals large enough to read from the back of a room
- Rehearsal, including the questions they expect to be asked and the ones they hope not to be
- Invitations to school leadership, teachers, parents, and any external guest such as the school counselor or a local health professional
- Promotion inside the school, aimed at the students who logged their sleep for three weeks
- The pajama dress code announcement
Close
The Results Reveal: The school gets its data back.
Recommend a pajama dress code for the event. Pajamas, slippers, a pillow if the room allows it. This is not decoration. It signals that this is the school’s own study coming home, lifts attendance, and it makes an event about biology feel like it belongs to everyone in the building.
Teams present the participation numbers, main findings and biology behind them, limits of the study, and recommendations. They take questions from the audience, including from the participants themselves.
Close the event by handing the recommendations to the people who can act on them.
Reflection: After the event, students reflect on the science and on the experience of running a real study. What surprised them. Where the data contradicted their expectations. What they would redesign in the instrument. How their own habits look to them now.
They also face the harder question. Knowing what the biology says is not the same as changing behavior, and getting people to participate turned out to be harder than getting the science right. What would actually have to change, at home or in the school, for their recommendation to work?
Final Dish
Serves
Students who are ready to stop hearing about sleep and start running the study.
