Scholarships are gift aid, so in almost every case you keep the money and owe nothing. Repayment becomes possible only in specific situations: you withdraw mid-term, your enrollment status drops, or you break a written condition of the award.
Knowing exactly where those lines sit is what protects families from a surprise bill halfway through a semester. Below is what triggers repayment, what does not, and what to do if your school asks for money back after funds were already applied.