REI Co-op Tarn 40 Review: Pack Grows With Your Child

REI built the Tarn 40 for kids. But while the REI Tarn 40 is a starter backpack meant to grow with children, it’s still made with durability, comfort, and utility in mind.

I started a new routine last summer. I’m bringing each of my children out on a one-on-one trip — somewhere in Idaho with dad, their choice. Their go-to response is usually backpacking. With miles upon miles of wilderness and BLM land, we have infinite choices.

As my kids have grown (stronger and more independent), I’ve slowly migrated equipment off my back and onto theirs. In other words, I’ve given up on carrying their sleeping bags, treats, and toys from home. In turn, I’ve promised they no longer need to haul their pokemon school backpack on an overnighter.

Climbing With Kids: Tips for Multipitch Routes
Climbing With Kids: Tips for Multipitch Routes
Ready to take your child on a multipitch adventure? Our contributor breaks down a few tips to make climbing with kids safe and easy. Read more…

But because kids grow like summer wildfire, I’m not interested in buying a new pack year after year. Fortunately, there are options. And one of them, REI’s Tarn 40 in the Graystone color option, is on sale right now for $70 (down from $110). Here’s our experience with the Tarn 40.

Review: REI Tarn 40

The Tarn 40 is a fully-kitted backpack. It doesn’t skimp on materials, straps, cushioning, or design. It’s a “real-deal” grownup backcountry pack capable of multiday excursions in the hills.

The internal frame is a top-loading pack with a floating (and removable) lid. A “keeper” cord snaps over the pack’s body and can cinch down bloated burdens or stow a puffy (or stuffy).

REI Co-op Tarn 40 child backpack review

A pair of “Z” compression straps thread down each side of the pack and can hold poles or rods, or simply slim the pack so it sits closer to the torso. 

The pack is hydration compatible, with a clip to hang a bladder from and left and right ports for the tube.

Two mesh pockets sit at the base of each side and are large enough to keep a 1-liter water bottle (or found rocks). Rounding out the pack body is a giant stretchy stuff-it pocket that overlays the back panel.

REI Co-op Tarn 40 child backpack review

The Tarn’s body rides on a well-padded harness with a Velcro adjustable shoulder harness that slides 4 inches, adjusting between 12 and 16 inches. The padded waist belt (with two zippered pockets — perfect for Jelly Bellies) slides from 22 to 36 inches.

The 16-inch mark is often the cutoff for packs in adult size small, and the Tarn bridges the gap from youth to adult.


REI Co-op Tarn 40 child backpack review

My daughter tested REI’s Tarn 40 on an 8-mile backpacking trip into Idaho’s White Clouds. While the nearby Sawtooths get all the play, the White Clouds are where it’s at. The trails are much less rocky, the views are infinitely broader, and the crowds are suspiciously smaller.

The trail starts at nearly 9,000 feet, climbing upwards to 9,500 feet before plunging down loose scree along switchbacks to the Born Lakes.

My daughter is petite: long legs, shorter torso, scraping the bottom end of the growth chart. So finding a pack that fits hasn’t been easy.

Before departing, we discussed what she should carry: a sleeping bag and pad, change of clothes, some food, and water. With several seasons of experience, she’s got the essentials down.

REI Co-op Tarn 40 kid's backpack review

The hike in was a bit of a grunt; we took our time. After stopping to adjust the pack’s shoulder, hip, and chest straps, we lallygagged the 4 miles in three hours.

REI Co-op Tarn 40 kid's backpack review

On the way out, I emptied her water bladder and moved the remaining food to my pack. She kicked up her heels and literally ran out most of the way. Oh, youth. Well, youth and not having to carry much water.

An 11-Year Old’s Take

I like how sturdy it is. And since it can be adjusted, I know I’ll be able to use it for years to come. Most kids will like the quality of the Tarn. It looks and feels like an adult backpack.

With so many straps, I did find that it’s hard to adjust. A child will need help making sure the straps and clips are adjusted to fit their body.

Thoughts From Dad

At 40 liters, this pack is about the right size for a child. It’s a size we’d recommend even adults consider if striving to cut pack weight. It’s just enough to hold a sleeping bag, pad, and a change of clothing yet small enough to rethink bringing that framed picture of Justin Bieber.

A toiletry kit easily fits in the top lid pocket. And the kids get a kick out of having quick access to food in the mesh hip-belt pockets.

For longer trips on the trail, if you dedicate the main pack to food, a pair of bottom straps can lash a sleeping bag or tent.

Parting Thoughts

REI Co-op Tarn 40 kid's backpack review

If you’re a backpacker and a parent, eventually you’ll want to bring your child into the hills. There’s no better experience than seeing the wonder of the outdoors through the fresh eyes of your child. And there’s no greater misery than seeing the outdoors through the eyes of an unhappy child.

Fortunately, kids are resilient critters — more so than adults. But an ill-equipped camper only takes away from the enjoyment, widening the gap between future outdoor adventures.

REI’s Tarn 40 is a great way to help push kids out on their own for years to come without breaking the bank.

Steve Graepel

Steve Graepel is a Contributing Editor and Gear Tester at GearJunkie. He has been writing about trail running, camping, skiing, and general dirtbagging for 10+ years. When not testing gear with GearJunkie, he is a Senior Medical Illustrator on the Neurosurgery Team at Mayo Clinic. Based in Boise, Idaho, Graepel is an avid trail runner, camper, angler, cyclist, skier, and loves to introduce his children to the Idaho outdoors.