Dive Summary:

• Researchers at Northwestern University found "strong and con­sis­tent evidence" that students performed better when their instructor was not on the ten­ure track.
• The study looked at students who in their first term took an introductory course in one subject taught by an untenured instructor and an introductory course in another topic with a professor who was tenured or on the tenure track; researchers then looked at their performance in subsequent classes on those topics.
• One important factor to note: 99.4% of the untenured faculty members in the study had been teaching at the university for at least six quarters.

From the article:

... "A nontenure-track fac­ul­ty mem­ber in­creases the like­li­hood that a stu­dent will take an­oth­er class in the sub­ject by 7.3 per­cent­age points," the authors wrote, "and in­creases the grade earned in that sub­se­quent class by slight­ly more than one-tenth of a grade point." ...