HOMEWORK STINKS!

It absolutely sucks to have to spend hours doing a 400 college level math class homework, then spend hours writing it up to total 13 pages, then spend several more hours writing it up AGAIN because it's 'lost'. Can someone explain to me how this can happen: you finish working on an assignment, stick it on your folder, put the folder in your backpack, not take it out until several hours later .... and find the assignment missing???????