Hi @elizabethnathan and welcome to the Seller Community! 

Once you've rung up all your sales, you can view your full sales reports from the app under Transactions or from the Dashboard on www.squareup.com under Reports. 

We would recommend probably making a specific item and name it something that would help you correlate it to them mentioning the school so that later you can see all your sales and which ones were customers that mentioned the school.

That would probably be the easiest/only way to go about that.