Marcos E. García-Ojeda wants to improve his teaching. He has flipped his classroom and embraced active-learning techniques. And he’s even invited some observers to sit in on his “General Microbiology” class here at the University of California at Merced on a recent afternoon.The observers will give Mr. García-Ojeda, an associate teaching professor of biology, a detailed depiction of the teaching and learning in his class — actions that are central to a college’s purpose but rarely examined.This examination is especially unusual because of who’s performing it: undergraduates. The observers — three current students and a recent graduate — are part of a program called Students Assessing Teaching and Learning, or Satal. And they have been trained in an array of techniques: observations, interviews, focus groups.Professors may be fond of students, on balance. But if an interloper wanted to blend in at a faculty gathering, casually dismissing the opinions of undergraduates would be a convincing approach. Course evaluations? Useless. Designing a college around students’ needs? Selling out.