Scholars are motivated by the pursuit of better quality in higher education. Searching for significant factors which can improve the performance of university students, they determined peer effects to be a determining factor.

The pursuit of better quality higher education is motivating scholars to search for significant factors which can improve students university performance. Peer effects are one of those factors under investigation.

Scholars are looking for ways to improve higher education, including ways peers influence it.

The pursuit of better quality in higher education is motivating scholars to search for factors to improve the performance of university students--peer effects, in particular.

The statement isn't clear. Is the story most about peer effects, or is it most about attempts to improve higher education? Assuming that you are trying to introduce peer effects, I'd consider Scholars are examining peer effects in the performance of university students. Scholars have determined that peer effects are significant in the performance of university students. Peer effects are significant in the performance of university students.