I have all my materials in 3 ring binders. Probably a total of 12 binders (1 per marking period for 3 courses). I want to be able to lock up these materials so that weekend guests to our classroom cannot access my materials. I have been storing these in drawers of a filing cabinet, but my I have filled up my file drawers and need to spill over into the drawers currently housing my binders. Any ideas where to find some sort of locking cabinet (where I could place the binders on shelves) or locking drawer unit that is not SUPER expensive. When I look in office supply stores they are usually over $150..... Thanks!