Is there somewhere that I can drop off old plates without standing in line? These plates are not mine so AAA won't take them.

Any dmv w the clerk at the greeting desk...or plate dept at cranston 1st floor left

Make sure you bring the vehicle registration or documents proving who owns the vehicle -- a copy of the owner's license will do. If there is no documentation of the registered owner, the plates will NOT be cancelled. They will remain active until the expiration date. Fees will remaim due.

If their not your plates you could mail them in but if they disappear or get stolen the person who had them would be responsible for any fines on the plates. So you're better off bringing them to the DMV.