I am thinking about buying a bookbag made by "burton" it is called a "day hiker" and i didnt know if it would be big enough for a 1.5" ring binder and like 4 medium sized books and and shirt and shorts. the bookbag is 29 liters and if you need more information you can go to Burton.com and then go to gear and then go to bags then go to snowboard packs then go to Day Hiker