Making use of a program called spamassassin, all messages delivered to simons-rock.edu addresses are tagged with a header which indicates a calculated likelihood that the message is spam. As these messages aren't blocked (because doing so might block some non-spam as well), it's up to you and your mail client to decide what to do with these tags.
You can create a spam folder and, by making use of filtering rules, have all of these tagged messages sent to the spam folder/mailbox, rather than be listed in your normal list of incoming mail. You'll still have to look through this folder on occasion to make sure that legitimate mail isn't making its way there, but it should cut down on the amount of spam you have to see on a daily basis. (Also, if you send email to spam when messages are being wrongly marked we can hopefully improve the tagging.)