80/80 Rule

During a H.E.A.T./H.E.A.R.T. walkthrough, how do you accurately gauge the indicators embedded in  the rubric? If one student asks a question in the higher cognitive zone, do you automatically score the level of student cognition for the entire class at the higher level based on one student's response? Conversely, do all students in the classroom have to demonstrate a particular level in order for you to score that category?

Using the 80/80 rule can help to minimize reliability issues and give the teachers an accurate picture of their classroom instructional practices. The 80/80 rule means that you are observing what 80% of the students are doing 80% of the time. This approach tends to eliminate outlier scoring and focus on the essence of the instructional dynamics between the teacher and the majority of students. The rule is particularly helpful when there is a wide continuum of learners in the classroom.