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← Why school should start later for teens

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Showing Revision 10 created 05/18/2017 by Brian Greene.

  1. It's six o'clock in the morning,
  2. pitch black outside.
  3. My 14-year-old son
    is fast asleep in his bed,
  4. sleeping the reckless,
    deep sleep of a teenager.
  5. I flip on the light and physically
    shake the poor boy awake,
  6. because I know that,
    like ripping off a Band-Aid,
  7. it's better to get it over with quickly.
  8. (Laughter)

  9. I have a friend who yells "Fire!"
    just to rouse her sleeping teen.

  10. And another who got so fed up
  11. that she had to dump cold water
    on her son's head
  12. just to get him out of bed.
  13. Sound brutal ...
  14. but perhaps familiar?
  15. Every morning I ask myself,

  16. "How can I --
  17. knowing what I know
  18. and doing what I do for a living --
  19. be doing this to my own son?"
  20. You see,
  21. I'm a sleep researcher.
  22. (Laughter)

  23. So I know far too much about sleep

  24. and the consequences of sleep loss.
  25. I know that I'm depriving my son
    of the sleep he desperately needs
  26. as a rapidly growing teenager.
  27. I also know that by waking him up
  28. hours before his natural
    biological clock tells him he's ready,
  29. I'm literally robbing him
    of his dreams --
  30. the type of sleep most associated
    with learning, memory consolidation
  31. and emotional processing.
  32. But it's not just my kid
    that's being deprived of sleep.

  33. Sleep deprivation among
    American teenagers is an epidemic.
  34. Only about one in 10 gets
    the eight to 10 hours of sleep per night
  35. recommended by sleep scientists
    and pediatricians.
  36. Now, if you're thinking to yourself,
  37. "Phew, we're doing good,
    my kid's getting eight hours,"
  38. remember,
  39. eight hours is
    the minimum recommendation.
  40. You're barely passing.
  41. Eight hours is kind of like
    getting a C on your report card.
  42. There are many factors
    contributing to this epidemic,

  43. but a major factor preventing teens
    from getting the sleep they need
  44. is actually a matter of public policy.
  45. Not hormones, social lives or Snapchat.
  46. Across the country,
  47. many schools are starting
    around 7:30am or earlier,
  48. despite the fact that major
    medical organizations recommend
  49. that middle and high school
    start no earlier than 8:30am.
  50. These early start policies
    have a direct effect on how much --
  51. or really how little sleep
    American teenagers are getting.
  52. They're also pitting
    teenagers and their parents

  53. in a fundamentally unwinnable fight
    against their own bodies.
  54. Around the time of puberty,
  55. teenagers experience a delay
    in their biological clock,
  56. which determines when we feel most awake
    and when we feel most sleepy.
  57. This is driven in part by a shift
    in the release of the hormone melatonin.
  58. Teenagers' bodies wait to start releasing
    melatonin until around 11pm,
  59. which is two hours later than what
    we see in adults or younger children.
  60. This means that waking a teenager up
    at 6am is the biological equivalent
  61. of waking an adult up at 4am.
  62. On the unfortunate days
    when I have to wake up at 4am,
  63. I'm a zombie.
  64. Functionally useless.
  65. I can't think straight,
  66. I'm irritable,
  67. and I probably shouldn't be driving a car.
  68. But this is how many American
    teenagers feel every single school day.
  69. In fact, many of the, shall we say,
  70. unpleasant characteristics
    that we chalk up to being a teenager --
  71. moodiness, irritability,
    laziness, depression --
  72. could be a product
    of chronic sleep deprivation.
  73. For many teens
    battling chronic sleep loss,
  74. their go-to strategy to compensate
    is consuming large quantities of caffeine
  75. in the form of venti frappuccinos,
  76. or energy drinks and shots.
  77. So essentially,
  78. we've got an entire population
    of tired but wired youth.
  79. Advocates of sleep-friendly
    start times know

  80. that adolescence is a period
    of dramatic brain development,
  81. particularly in the parts of the brain
  82. that are responsible for those
    higher order thinking processes,
  83. including reasoning, problem-solving
    and good judgment.
  84. In other words, the very type
    of brain activity that's responsible
  85. for reining in those impulsive
    and often risky behaviors
  86. that are so characteristic of adolescence
  87. and that are so terrifying
    to us parents of teenagers.
  88. They know that like the rest of us,
  89. when teenagers don't
    get the sleep they need,
  90. their brains, their bodies
    and behaviors suffer
  91. with both immediate and lasting effects.
  92. They can't concentrate,
  93. their attention plummets
  94. and many will even show
    behavioral signs that mimic ADHD.
  95. But the consequences of teen sleep loss
    go well beyond the classroom,

  96. sadly contributing to many
    of the mental health problems
  97. that skyrocket during adolescence,
  98. including substance use,
  99. depression and suicide.
  100. In our work with teens
    from LA Unified School District,
  101. we found that teens with sleep problems
  102. were 55 percent more likely
    to have used alcohol in the past month.
  103. In another study with over
    30,000 high school students,
  104. they found that
    for each hour of lost sleep,
  105. there was a 38 percent increase
    in feeling sad or hopeless,
  106. and a 58 percent increase
    in teen suicide attempts.
  107. And if that's not enough,
  108. teens who skip out on sleep
    are at increased risk
  109. for a host of physical health problems
    that plague our country,
  110. including obesity,
    heart disease and diabetes.
  111. Then there's the risk
    of putting a sleep-deprived teen,
  112. with a newly minted driver's license,
  113. behind the wheel.
  114. Studies have shown that getting five hours
    or less of sleep per night
  115. is the equivalent of driving with a blood
    alcohol content above the legal limit.
  116. Advocates of sleep-friendly start times,

  117. and researchers in this area,
  118. have produced tremendous science
  119. showing the tremendous benefits
    of later start times.
  120. The findings are unequivocal,
  121. and as a sleep scientist,
  122. I rarely get to speak
    with that kind of certainty.
  123. Teens from districts
    with later start times get more sleep.
  124. To the naysayers who may think
    that if schools start later,
  125. teens will just stay up later,
  126. the truth is,
  127. their bedtimes stay the same,
  128. but their wake-up times get extended,
  129. resulting in more sleep.
  130. They're more likely to show up for school;
  131. school absences dropped
    by 25 percent in one district.
  132. And they're less likely to drop out.
  133. Not surprisingly,
    they do better academically.
  134. So this has real implications
    for reducing the achievement gap.

  135. Standardized test scores
    in math and reading
  136. go up by two to three percentage points.
  137. That's as powerful as reducing class sizes
    by one-third fewer students,
  138. or replacing a so-so teacher
    in the classroom
  139. with a truly outstanding one.
  140. Their mental and physical health improves,
  141. and even their families are happier.
  142. I mean, who wouldn't enjoy a little
    more pleasantness from our teens,
  143. and a little less crankiness?
  144. Even their communities are safer
  145. because car crash rates go down --
  146. a 70 percent reduction in one district.
  147. Given these tremendous benefits,

  148. you might think,
  149. well, this is a no-brainer, right?
  150. So why have we as a society
    failed to heed this call?
  151. Often the argument against later
    start times goes something like this:
  152. "Why should we delay
    start times for teenagers?
  153. We need to toughen them up
    so they're ready for the real world!"
  154. But that's like saying
    to the parent of a two-year-old,
  155. "Don't let Johnny nap,
  156. or he won't be ready for kindergarten."
  157. (Laughter)

  158. Delaying start times also presents
    many logistical challenges.

  159. Not just for students and their families,
  160. but for communities as a whole.
  161. Updating bus routes,
  162. increased transportation costs,
  163. impact on sports,
  164. care before or after school.
  165. These are the same concerns
    that come up in district after district,
  166. time and again around the country
  167. as school start times are debated.
  168. And they're legitimate concerns,
  169. but these are problems
    we have to work through.
  170. They are not valid excuses
  171. for failing to do the right thing
    for our children,
  172. which is to start middle and high schools
    no earlier than 8:30am.
  173. And in districts around the country,
  174. big and small,
    who have made this change,
  175. they found that these fears
    are often unfounded
  176. and far outweighed by the tremendous
    benefits for student health
  177. and performance,
  178. and our collective public safety.
  179. So tomorrow morning,

  180. when coincidentally we get
    to set our clocks back by an hour
  181. and you get that delicious
    extra hour of sleep,
  182. and the day seems a little longer,
  183. and a little more full of hope,
  184. think about the tremendous power of sleep.
  185. And think about what a gift it would be
  186. for our children to be able
    to wake up naturally,
  187. in harmony with their own biology.
  188. Thank you,

  189. and pleasant dreams.