调整

app/controllers/homework_commons_controller.rb

@@ -206,7 +206,7 @@ class HomeworkCommonsController < ApplicationController
         else
           @student_works = @student_works.includes(:student_works_scores, :project, user: :user_extension)
         end
-        @students = @course.students.where(user_id: @student_works.pluck(:user_id)).preload(:course_group)
+        @students = @course.students.preload(:course_group)
       end
 
       if params[:format] == "xlsx"