Yet another reason to make sure your child is getting enough sleep.
Those who don't are more likely to be "bad classmates."
Researchers studied kids (11 years old and younger), who were either put to bed 30 minutes earlier than normal or 30 minutes later than normal.
The kids who got less sleep were more impulsive, irritable, frustrated, and quicker to cry.
Experts say elementary school children need 10-to-11 hours of a sleep every night.
