I agree. Standard advice is don't put money on the stock market unless your time horizon is 5 years or more, because you can easily be underwater in the short term, especially if we go into a recession.
Retirees and people who will need their money soon should generally pick something safe and secure. With a one-year CD you will keep pace with, or slightly beat inflation, and the money will be there when you need to pay off your students loans.
When you pay them off, you will get a guaranteed savings of whatever interest rate you are paying off, say 5% or 7%. What are your rates?
www.bankrate.com for best national rates. You might want to pick a 1 year or 6 month CD and just roll it over, as rates seem to be rising.