(NewsNation) — It’s back-to-school time, and students across the country are gearing up to head back to the classroom. For some, it’s an exciting time, and for others, a time of stress and anxiety.

A new classroom, new friends — and potentially — old bullies. Experts say there is no shortage of reasons why your child may be nervous about heading back to school.

“There are so many changes that are brought about once we bring back the school year that it would be really normal and expected to have some of that nervousness, and perhaps anxiety, leading into the start of the school year,” said Emily Dienst of Northwestern Medicine.

For many kids, back-to-school jitters can be chalked up to a new school or worry about making new friends, and the jitters end pretty quickly. For other kids, the anxiety can be debilitating.

Some of the symptoms include repeated episodes of sudden, unexpected, intense fear that come with symptoms like heart pounding, having trouble breathing or feeling dizzy, shaky or sweaty.

“Our brain is telling us that there is something unsafe going on,” said Dienst. “So similar to if we were sitting in a room and there was a lion, and our heart rate starts to elevate, our breathing becomes more shallow … sometimes, then, our brain applies that to situations where safety really isn’t an issue.”

According to Mental Health First, one in five youth will experience a mental health challenge at some point in their life, and about 17 million youth under the age of 18 have or have had a psychiatric disorder. Every year more than 7% of kids have a mental health visit.

But what can you do?

According to experts, help starts by talking to your kids to find out what’s wrong and validate what they are experiencing — in their mind, the fear is real.

“Actually, one in four kids right now are diagnosed with some kind of anxiety or depression. The needs have really gone up as far as mental health needs,” said Cathey Steadman, a student wellness specialist.

Experts advise children to hang out with friends before school begins and set up play dates so they feel comfortable with kids they’ll likely see on the school bus or in the classroom. And, by all means, make sure they go to school and help them face their fears.

“Starting that school year with a lot of encouragement. Everybody wants that youth to be successful and to feel valued,” Dienst said.