We have a webserver that can give a student credit if they pass or fail a lesson. We don't have a lot of lessons with quizzes. We have some new projects coming up where they want the student's grade on the quiz to be recorded. For example, the student made a 45% out of 100.
Simple answer is that you won't be able to track your user's results without LMS. Get open source LMS in case you do not have budget for it.
If you have a programmer handy you can set up a mySQL database on the server and write some JS with PHP to send the student name, ID, and quiz scores to the database. Failing that, I agree with @alfredmack
How are you tracking completion now? Just extend that to include test score, which you can pass from your Cap project.