Final answer:
A teacher assuming all Catholic families are over-involved in their kids' lives is engaging in stereotyping, which can lead to misunderstandings and negative educational effects.
Step-by-step explanation:
A teacher who thinks that all Catholic families are over-involved in their kids' lives is engaging in stereotyping. This is a form of generalization that ascribes a fixed set of characteristics to all members of a group, based on some observable or assumed traits of a few members of that group. Stereotypes can be based on a range of characteristics including ethnicity, religion, gender, or socioeconomic status, and are often considered a biased viewpoint. While it's important for teachers to understand the backgrounds and cultures of their students, stereotypes can lead to misunderstandings and prejudiced attitudes, which can affect the educational environment and student-teacher relationships negatively.