1. Inform the class that students will be collecting data about their own sleep habits over the next 10 days. Explain that sleep medicine specialists use similar information to provide insight into a patient’s sleep patterns.

The sleep diary in this activity is simplified and deals only with sleep/wake times and the consumption of caffeine-containing beverages. From more extensive sleep diaries, scientists and doctors who study sleep can also learn about how environmental factors, emotions, medications, or drugs affect sleep. Such data can help a doctor investigate whether the individual suffers from a sleep disorder or from inadequate sleep due to a very busy schedule.

Sleep diaries rely on self-reporting, which may not always be accurate. Also, some important symptoms of sleep disorders, such as breathing problems, snoring, and excessive body movements, occur during sleep and therefore aren’t reported by the individual.

Sleep specialists also use sleepiness scales in analyzing sleep issues, but the one in this activity should not be used to assess your students’ health.

2. Give each student one copy of both Master 0.1, Sleep Diary, and Master 0.2, Recording Bedtimes and Wake Times. Ask students to first look at Master 0.1. Inform them that they will be recording the times that they go to bed at night and wake up in the morning for 10 days, beginning with bedtime on that night (the Friday they receive their copies). Explain that they will record these times to the nearest quarter hour. For example, if a student goes to bed at 10:25 p.m., he or she would say bedtime was 10:30 p.m. Also explain that they will need to record the total number of hours they slept each night, the number of times they remember waking up during the night, and the number of caffeine-containing drinks (coffee, tea, colas, or other caffeinated beverages) they consumed during the day.

Make sure students understand that wake time refers to the time in the morning when they awoke for the day. It does not refer to the times during the night when they may have awakened for a brief period. Also, remind students to record the number of caffeine-containing drinks they consume each day.

3. Give each student one copy of Master 0.3, Sleepiness Scale. Explain that scientists who study sleep use charts like this to gather information about just how sleepy people are at different times of the day.

As with aspects of the sleep diary, this relies on self-reporting rather than a completely objective measure. Encourage students to respond as accurately as possible.

4. Instruct students to look at Master 0.3, Sleepiness Scale. Explain that on day 4 (a Monday), day 7 (Thursday), and day 11 (the second Monday), they will need to record how sleepy they are at different times during the day. At the times listed on the chart on Master 0.3, students will judge how sleepy they are and base their responses on the information in the chart at the top of Master 0.3.

You may elect to change the times requested for data entry, but only as follows. The 10:00 a.m. time can be adjusted to correspond with first or second class periods, and the 2:00 p.m. time can be adjusted to correspond with the end of the school day. These times were selected to maximize the chance of detecting the morning rise in alertness and the midafternoon dip in alertness.

5. You might draw the following diagram on the board to illustrate the tasks the students have and when they should be accomplished:

6. On the Friday (day 8) of the week during which students are collecting their data, remind them that they will need their sleep diary and their sleepiness scale data with them on Monday (day 11) so that they can begin to analyze and evaluate their data.
7. Explain to students that calculating an average bedtime or average wake time is somewhat complicated by our system of telling time (24 hours in a day, 60 minutes per hour, and a.m. vs. p.m.). Instruct students to use Master 0.4, Calculating Average Bedtime and Wake Time, to obtain their average values. Students should also calculate their average total sleep time, average number of awakenings during the night, and average number of caffeine-containing drinks consumed.

Calculating the average bedtime and average wake time is complicated, but the worksheets should guide students through these calculations. Calculating the averages for total sleep time, number of awakenings, and caffeinated drinks is much more straightforward. If, however, you feel it is appropriate for your students, review how to calculate an average with them.

8. Students should keep their copies of Master 0.1, Sleep Diary, and Master 0.3, Sleepiness Scale, for use in later lessons.