Youre right. There arent tons of youth packs out there, in large part because there just isnt much market for them. Backpacking kids are relatively rare, and in most cases mom and dad get wheedled in schlepping the gearor they do so voluntarily to reduce the whining quotient.
So your grandkids are the exception, and Im please to see them so interested in getting outdoors. And there are indeed some packs that would work for them. Sort of the boilerplate pack for youngsters is the Kelty Yukon 2900 ($110). Its a classic external-frame design, which is actually a good design for a kids pack because it can be telescoped as the child grows. Torso length, in fact, can be adjusted from 13 to 19 inches. Capacity is pretty good at 2,900 cubic inches. And there are plenty of pockets for kids to placeand losetheir stuff. JanSport makes a similar pack called the Scout Pack ($90). On the internal frame side, Deuter makes the Fox 30 ($79), an 1850-cubic-inch pack that can support loads of up to 20 pounds.
As the grandkids grow, put the biggest one into The North Face Terra 55 Youth pack ($129). Its a more modern internal-frame design, for more comfort and load-carrying capacity (3,350 cubic inches). It can then be handed down, and when that happens, the first to use it will have grown into small adult packs.
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