If you are the curator of the school art show, you choose which pieces will be in it and decide how they will be displayed. A curator is someone who manages an art collection or exhibit.
The kind of artwork a curator manages does not have to be the visual kind. You can curate a series of readings by selecting which authors read in it and who reads together. A curator is the person who gives the overall shape and feel to an art exhibit. In law, if you are the curator of someone's estate, you have been given legal power to manage it for someone who is too young or mentally unable to do it themselves.