Ask any parent and they can tell you that when their kids don't get enough sleep, they are cranky with a capital 'C' the next day. That one's kind of a no-brainer. But a new study claims that when kids get random amounts of sleep — early bedtime one night followed by a late night the next — they can be just as cranky if not even more so.

For the study, researchers looked at the sleep patterns of over 10,000 British school children at ages 3, 5, and 7. Parents were asked about the regularity of kids' bedtimes, particularly during the school week as well as information about their children's conduct problems, hyperactivity, emotional symptoms, or ability to get along with peers. Teachers were also given the opportunity to weigh in on each child's behavior once they were in school.

It came as no surprise that kids with a late bedtime — after 9 p.m. — had more behavior issues than their early-to-bed peers. But what was surprising was that kids with random bedtimes actually had more behavior problems even than the kids who regularly got an abrupted night's sleep. You can read all of the details of the study in this post: Want well-behaved children: Put them to bed on time?

These results fall right in line with the study I wrote about this summer that found kids with irregular bedtimes had lower test scores in school.

As a home-schooling parent, I was curious about the results of this study because the assumption is that it is the random bedtime that makes kids cranky. But what if your kids have a random bedtime but still get a regular amount of sleep each night? I am curious to know if these results would still stand. It's possible that its the randomness of the bedtime that makes kids cranky. But I would argue that it's the irregularity in the amount of sleep that's causing the problem — and that's not the same thing.

I certainly concede that most kids in the developed world have to get up at a regular time each morning for school. But there are also plenty of kids that don't. It would be interesting to know if any of the 10,230 kids involved in this study were home-schooled and if so, how the irregular bedtime affected their behavior - if it affected it at all.

For instance this study, conducted by researchers at National Jewish Health in Denver, Colo., looked at the total amounts of sleep that kids got each night and how it affected their ability to learn. Of the 2,612 students evaluated, 500 were home-schooled. And the study found that these home-schooled students slept an average of 90 minutes more per night than their peers. Overall, the study found that 55 percent of kids who were home-schooled got the optimal amount of sleep each night compared to 24.5 percent who attended a traditional public or private school.

I know it's a fine point and one that really doesn't matter when your kids have to get up at the same time each morning. But for those kids that don't, I think it's incorrect to assume that it's the randomness of bedtime that is the issue.

What do you think?

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