Box 2 in Form 1099-Q represents earnings. Here is a link to information on the IRS website. Earnings are things that are outside of tuition, books, and school essentials. Usually that would be something like room and board / rent, and living expenses. This is because books and tuition are considered necessary for education; living expenses and food is something everyone needs regardless of whether they are receiving a college education or not. Those items are considered "income" for federal tax purposes, and are taxable as such. Books, tuition and the like are not.
Here is a TurboTax article with guidance regarding Form 1099-Q.
