Visit national parks for free with Every Kid Outdoors. Here’s how.

Millions of families are missing out on a major travel perk, just for having a kid in the fourth grade.

The government’s Every Kid Outdoors program grants families with fourth graders free access to public lands and waters all across the country, including national parks.

“We chose fourth graders because research shows that kids ages 9 to 11 are beginning to learn about the world around them. They're open to new ideas, and they are likely to connect to nature and our history,” the program’s website states. “Over time, every kid can get a free pass to explore our country.”

More than 120,000 Every Kid Outdoors passes were issued between Sept. 2021 and Aug. 2022, according to the program’s latest annual report, but more than 3.9 million U.S. families would have qualified. That’s how many fourth graders were enrolled in public schools the same year, according to the National Center for Education Statistics, not including private school and home school students.

Here’s what families should know about the free program.

What is Every Kids Outdoors?

Every Kid Outdoors is designed to make the outdoors accessible to all families and inspire the next generation of stewards.

“Research on (Every Kid Outdoors) participants indicate that without free access, most (73%) would never have visited a national park,” its annual report says. ”Research also shows that participants are more likely to visit parks throughout the rest of their lives if they experience parks with their family or school at age 10.”

The program was first launched as Every Kid in a Park in 2015 and has been authorized by Congress through 2026.

How does Every Kid Outdoors work?

Fourth graders simply have to sign up on everykidoutdoors.gov and then print out a pass to take to their desired federal recreation site. No further proof or documentation is required, but students must check a box attesting to being a fourth grader or the home school equivalent. Some sites will swap out the paper pass with a plastic one, but electronic copies will not be accepted.

The passes cover entry for the fourth grader and up to three accompanying adults and all kids under age 16. They don’t cover fees for camping, or tours or other things.

They may be used in areas managed by the National Park Service, National Oceanic and Atmospheric Administration, U.S. Army Corps of Engineers, U.S. Bureau of Land Management, U.S. Bureau of Reclamation, U.S. Fish and Wildlife Service and U.S. Forest Service.

“No matter where you live in the United States, there’s a site within two hours of your home,” according to the program’s website.

How long is the pass valid?

The pass is good for the fourth grader’s entire academic year and the most of the following summer.

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What if I don’t have a fourth grader?

The passes are non-transferable, but other visitors aren’t entirely out of luck.Not all federal lands charge entry fees. And the National Park Service offers a handful of free admission days every year.

This article originally appeared on USA TODAY: Millions of families can visit national parks for free. Here’s how.