Look at the two maps

How Much Do Teachers Get Paid?

Source

There seems to be some relation between paying teachers well and high SAT scores. What I think of as the northern mid-western states have both good teacher salaries and high SAT scores.

 Of course, salaries are relative, and some states with low costs of living and relatively lower pay in alternative jobs make lower salaries more acceptable to teachers.

If a smaller portion of kids in a state apply to schools requiring SATs, then the average SAT score might be higher. That would be true if the smaller portion were the more academically gifted students in the state.

Correlation is not causation. It may be that some factor causes kids to score well and teachers to be paid well. For example, communities that value education highly might be willing to pay more to teachers and encourage kids more to excel in school.