My son is a junior and is ranked first in his class. He is in advanced Math and Science programs, however, so far he has taken only one year of Spanish. Both positions are indications of terrific achievement. However, I am worried about your son's foreign language requirement.
Many schools require two to three years of language in high school.
Contact the schools you are considering and ask them specifically if having only one year of foreign language would create a deficit in your son's transcript. If you learn that he needs more Spanish, perhaps summer school could give him the second year free he needs and enable him to take Calculus in the fall.