There is a procedure for dealing with wheels that come to the co-op with tires on them. These wheels might come in on their own or come off of a scrap bike. However, if you work with tired wheels you will find them in the Tired Wheels pile, and it doesn't matter where they came from.
In the tired wheels pile there should be two sections: one for wheels that have been pumped up and one for wheels that have not. There are different procedures for the two.
For wheels that haven't been pumped up, pump them! You don't need to worry about inflating them to the right pressure, just go until they're hard, and then stop. You may overinflate one and blow it out, but then you'll learn not to do that. Afterward, if you mark them with the day you inflated them, it will allow someone to check them out later.
The rest should have been inflated by someone else a few days ago. Knowing that gives you information: you can tell if the tube has leaks by checking if they are still inflated. Whether the wheel you are working in is inflated or not, you will then remove the tire and make careful note of its size. Evaluate the tire if you can, or ask a key volunteer to evaluate it, and put it where it belongs. Now, if the wheel was still fairly inflated, put the tube in the drawer corresponding to its size, since you know it's good. If it was flat, hang the tube on the "tubes to check" hook. You do not need to inspect the tube.