Human brain needs break. It needs relaxation. If the brain is hyper-active all the times, your brain neurons are firing all the time. That may lead to many negative effects for example sleep apnea, anxiety etc.
Specially in growing kids, their brain is developing. Therefore, the brain needs quiet time so that the neurons can make new connections.
As we discussed, the kids have lots of things going on. Studies, homework, peer pressure, girlfriend, boyfriend etc. etc.
Many kids mistake distraction to be the relaxation. They use their break time to get into social media, watch YouTube, watch TV, play video games etc. Those things don’t bring relaxation to their brains. They bring more agitation to the brain.
There must be a certain minute of do-nothing time. Just lie down and do nothing for few minutes.
If they can meditate even for 10-15 minutes a day, that goes a long way.
Playing/listening music, cooking food, cleaning and doing household chores are also good ways to relax the brains.