In the US, the valedictorian of a high school is typically the person with highest academic grade point average. I've never heard of it considering sports part

In the US, the valedictorian of a high school is typically the person with highest academic grade point average. I've never heard of it considering sports participation, although Wikipedia does suggest that sometimes extra-curriculars are now being considered: https://en.wikipedia.org/wiki/Valedictorian https://en.wikipedia.org/wiki/Valedictorian. But given his age and absent outside information, I think the fair assumption is that he won because he had the best grades in his courses.