Are hours spent in company-paid evening classes considered overtime?

Q: “We have an employee who is currently considered exempt. However, when the new salary threshold goes into effect, he will be nonexempt. He is attending college classes during the day, and was hired upon the condition that he get a degree. The employer pays for his tuition. How are the hours he attends class handled when computing overtime? Since they are required, do they count toward his 40 hours per week?” - Susan, Tennessee