The body of knowledge available to Isaac Newton was not as large, but I doubt he was finding any excitement in linear functions. Also, the person discussed is a teacher, not a student. And I did offer Euclidean geometry as an option 🙂
I assume high-level math at high school includes topics like infinitesimal calculus and numbers theory and I would expect good teachers to get excited about Newton vs. Leibniz controversy or Fermat’s last theorem. I suppose I should assume less.