Yes, many colleges inform schools of acceptance/rejection/waitlist decisions.
This depends on individual counselors, the relationships they have with schools and how much outreach they are willing to do.
For high schools that use and colleges that participate in Slate, the school can log in to their slate account and see if students have been accepted/rejected.
CUNY just sent a report out yesterday to all NYC high schools on Friday listing all students from their schools who have applied to CUNY and the decision outcomes (this has been happening for over a decade) and is dine automatically.
Individual SUNY schools send out results list to counselors. You can request them if from your regional admissions person you don’t get them automatically
There are many private schools that send application results to high schools. Again, if your counselor has a relationship with their regional admissions person, all they have to do is ask.
Counselors can call schools and request a status report on their students.
Many schools require post secondary plans, at the NYC DOE, you must include a post secondary plan in order to discharge a student as a high school graduate.
The high school will send out one final transcript to a college.
The final transcript will need to be a sealed document that has the graduation date and discharge date (this year the documents will be accepted via the school’s email).