This can be annoying to those around you. If you smoke, do it outside, not in the bathrooms. If you or your children have a cold, postpone your visit. Sniffles and sneezes spread germs, no one wants them. Be considerate of others and they'll do the same.
Some centers allow only pencils and paper.
Lockers are usually provided for storage of personal belongings. Others, allow anything. Ask the receptionist if they have a tour. This is a great way to get started, learn what they have and where it's located. You won't remember everything, but you will have a better idea what that particular facility holds.