Always read and follow the care instructions and any warnings on the garment label. And, follow the General Rules for washable fabric stain removal.
The best way to deal with crayons is to get advice right from the horse's mouth....Crayola! See their removal tips at their web site.
For another option, here's what another source says: Scrape excess crayon with the dull edge of a butter knife.
Wash in hot, soft water with soap, such as Ivory and 1/2 cup baking soda for 10 minutes.
If the stain remains, work soap paste into the stain. Wash 5 minutes. Rinse.
To remove any remaining color use bleach or color remover as safe for the fabric. Always test for color fastness.
HANK'S SURPLUS TACTICAL ASSAULT 3 DAY BACKPACK
At only 4 pounds, Hank's Surplus packed a punch with its Assault 3 day Backpack. If it's an awesome assault pack you need, you’ll find it in the tactical Assault 3 Day Backpack. Made with super strong 500D CORDURA® Classic fabric, this bag is designed to endure anything and it comes with strong nylon webbing. For storage, this pack has three main compartments with two nylon mesh pockets and inside hydration pocket with drain port. Learn more about this technology. Shop for this technology>
MEN'S SOLID ACTIVE CAP
Dr. Cool's hats use a patented, chemical-free cooling mesh deigned by Coolcore- this lightweight billed cap will keep you cool, dry and comfortable in the sun. With an adjustable Velcro® band and moisture-wicking sweatband, this is the perfect hat for all your outdoor activities. Colors: Black, Monaco Blue, Red, and White. Learn more about this technology. Shop for this technology.