Spongebob Squarepants Backpack Set - Bundle with 16" Backpack, Water Bottle, Stickers, and More | Spongebob School Supplies for Kids. This Spongebob bundle includes a 16" backpack with adjustable shoulder straps, zip closure main compartment featuring colorful artwork of Spongebob Squarepants. Show off your love of Spongebob in style! This backpack set is sure to be a hit with all Spongebob fans and pairs perfectly with all other Spongebob merchandise. This Spongebob backpack for boys has plenty of room to carry everything a kid would need when attending school and extracurricular activities! Officially licensed Spongebob backpack set for kids, boys and girls alike, also includes a Beach Kids water bottle, Spongebob stickers, and a Beach Kids door hanger. For ages 3 and up!