Common sense would tell you that parents, and especially stay-at-home moms, look forward to the beginning of school in August so they can have some time away from hungry kids complaining that they're bored. Parents do often feel that way, but according to a study by three professors from Mississippi State University, mothers actually have a lot less free time during the school year.
On weekdays during the school year, moms average 25 minutes less sleep, 28 minutes less free time, and seven minutes less for exercise than they did during summer vacation. Fathers show this effect as well, but not as much.
See, during the school year, kids may be gone for six to eight hours, but every day requires a lot of prep, including getting children to bed at night and up in the morning, preparing breakfast (and maybe lunch), driving to and from school, managing extracurricular activities, and supervising homework. Generally staying on a strict schedule takes a lot of time and energy.
The data came from the American Time Use Survey. Younger children didn't participate in the time survey, but teenagers ages 15-17 did, and it shows that school drains their time sleeping and unwinding as well. Read more details on this study at The Conversation.