"学校评分方式" can be translated into English as "school grading system" or "school assessment method".
"School grading system" is more commonly used when referring to the overall framework or set of rules for assigning grades or scores in a school.
"School assessment method" emphasizes the specific techniques or approaches used to evaluate students' performance.
Both expressions are appropriate depending on the context, but "school grading system" is often the more straightforward choice when discussing the general mechanism of how students are graded.