Herschel backpack, sized for children. Great for preschoolers - it is roomy enough to fit their stuff (yes they do need to pack quite abit like spare set of various clothing, snack, waterbottle, or even a hat), but yet the straps are well padded should you need them to carry their own bag for awhile. Zips have been toddler tested and she can manage them easily.

These are sold online or only at certain Herschel stores. 11 colours to choose from too!