What exactly are you asking? In most cases, colleges do NOT contact the high schools when making admissions decisions. They expect that the student will have provided them with all the info needed.
If a student is hoping to get off of a waitlist, it’s sometimes helpful for the school counselor to contact the school usually to provide any updates achievements and to express the students high interest in the college.
I suppose a college could contact a school if there was conflicting information and they wanted a clarification…I have never heard if that happening.
Most college adcoms don’t have the time to call High Schools to inquire about applicants. The expectation is that the adcoms will see what they need to know to make those “difficult decisions” by looking at the college application the student has submitted.
@compiler why are you asking this now?