A New York City psychologist says that back-to-school time is also a time for kids to get mentally set.

"Start getting ready to go back to school even several weeks before school starts," says Dr. Angela Kang.

Kang says that even parents who procrastinate getting their kids ready for the school year don't need to worry.

"Even if you start the day before, that's obviously OK as well," she says. "Getting them back into a routine, especially because during the summer you're spending a lot of time out of routine, vacationing."

Kang also says parents should remember that school isn't just about the grades.

"They're making friendships, they're exploring things that they're interested in," she says.