astronomy

Start school later movement

Start school later movement is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Start school later movement rather than just read about it. In short: In the United States, the start school later movement is an interdisciplinary effort by health professionals, students, parents, and educators to shift school hours later. It bases its claims on a growing body of evidence that starting middle and high schools too early in the morning is unhealthy for teenagers.

Key takeaways

Start school later movement belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Start school later movement to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Start school later movement from memory before moving on to harder problems.

Reference excerpt

In the United States, the start school later movement is an interdisciplinary effort by health professionals, students, parents, and educators to shift school hours later. It bases its claims on a growing body of evidence that starting middle and high schools too early in the morning is unhealthy for teenagers. Since the second half of the 20th century, most public schools in the United States have started high school around 8:00 a.m., in some cases as early at 7:00 a.m. Before that, schools rarely began before 8:30 or 9 a.m. According to the CDC, school should begin no earlier than 8:30 a.m. for middle and high school students. Advocates of a return to later school start times argue that sleep is a public health issue. They say that early school start times cause widespread sleep deprivation among teenagers as well as physical, psychological, and educational problems. Not only do students consistently get significantly more sleep on school nights when their schools move to later start times, but later school hours have been linked with improved school performance, reduced impulsiveness, and greater motivation. They also cause lower rates of depression, tardiness, truancy, and morning automobile accidents. Studies from 2011 suggest that early school start times disproportionately hurt economically disadvantaged students and may even negatively impact future earning potential of students, offsetting any financial savings to the school system attributed to earlier hours. Therefore, many schools and two entire US states have implemented later school start times.

Context Since the rise of suburbs in the mid-20th century, most public secondary schools in the US have started around 8:00 a.m., and some start as early as 7:00 a.m. This is done for three reasons: it allows school districts to use the same fleet of buses and drivers for different grade levels, it allows older students to care for or transport younger siblings after school, and it avoids rush-hour traffic around 8:30 a.m. The CDC recommends that middle and high schools start at 8:30 a.m. or later, but less than 20% of such schools currently follow this guideline.

Origins In the early 1990s, the University of Minnesota's landmark School Start Time Study tracked high school students from two Minneapolis-area districts – Edina, a suburban district that changed its opening hour from 7:20 a.m. to 8:30 a.m. and the Minneapolis Public Schools, which changed their opening from 7:20 a.m. to 8:40 a.m. Many positive benefits to students were found, including:

Improved attendance and enrollment rates Less sleeping in class Less student-reported depression Fewer student visits to school counselors for behavioral and peer issues More even temperament at home A longitudinal follow-up study of the Minneapolis Public Schools after five years revealed that these and other positive benefits had persisted. In 2014, a three-year project using data from more than 9,000 students attending eight high schools in three states, found that when schools switched to a start time of 8:30 a.m. or later, attendance, standardized test scores and academic performance improved, and tardiness, substance abuse, symptoms of depression, consumption of caffeinated drinks, and the rate of traffic accidents involving teen drivers decreased. Since the 1990s over 250 individual schools or districts in 45 states have delayed their start times, and scores of others are considering a change at any given time. Despite sporadic reform efforts on the part of educators, public health officials, legislators, and grassroots groups, however, most American middle and high schools still require students to begin instruction prior to 8:30 a.m. Failure of efforts to delay start times over the years has primarily been due to pushback from community members who fear that a shift to later school hours will be prohibitively expensive and/or disrupt after-school sports and other extracurricular schedules, student jobs, daycare arrangement, teacher training, or time for homework.

Shifted circadian rhythms and sleep deprivation Proponents of a return to later school hours cite abundant evidence that starting middle and high school before about 8:30 or 9 a.m. is incompatible with the biological clocks of teenagers and young adults. In 1993, a team led by Mary Carskadon, PhD, of Brown University showed that changes in circadian biology during puberty drive a "sleep-phase delay," a shift in the sleep-wake patterns of adolescents that leads them to fall asleep and wake up later than younger and older people. Subsequent studies have confirmed these findings, explored the impact of school start times on the sleep needs and patterns of adolescents., and demonstrated a "phase shift" in the release of melatonin at puberty, which appears to be involved in shifting the sleep-wake cycle several hours later during the adolescent years. This same shift to a delayed phase in the release of melatonin during puberty has also been seen in other mammals. The shifted circadian rhythms associated with puberty make it difficult, if not impossible, for many teenagers—who may have to rise at 5 or 6 a.m. to get ready and commute to school in time for 7 a.m. school bells—to get sufficient sleep on school nights. Even discounting for the distractions of homework, extracurricular demands, and electronics, most adolescents find it difficult to fall asleep before about 11 p.m. or rise before about 8 a.m. In addition, they need to sleep in until 8 a.m. or so to get the 9 or more hours of sleep that most sleep research suggests they need. As a result, many teenagers arrive at school sleep-deprived. The most recent data from the Youth Risk Behavior Survey show that 70% of American high school students are sleep-deprived and about 40% get six or fewer hours of sleep per night. A study in the Minneapolis Public School District in 1997-1998 demonstrated that multiple sleep deprivation effects could be alleviated by delaying school start times. Factors such as attendance especially increased. Also, there was a decrease in disciplinary problems, indicating that chronic sleep debt also drove behavioral issues amongst the student population.

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with Start school later movement

Start with the simplest possible case. Write down what Start school later movement claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Start school later movement before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Start school later movement ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Start school later movement

In research: Start school later movement appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Start school later movement in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Start school later movement is common in secondary-school and first-year university syllabi. It links to neighbouring topics Children's health in the United States, Education policy in the United States, Education reform in the United States, so understanding it makes those chapters shorter.
In everyday life: Look for Start school later movement outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Start school later movement” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Start school later movement in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Start school later movement means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Start school later movement out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Start school later movement in simple terms?

Why does Start school later movement matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Start school later movement?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Start school later movement.