Same old management mantra:
1. Collect the information and decide what specific problems need to be addressed. 'Specific' means two things: firstly, problems which are a particular issue in your school, which may require changes to school monitoring systems and policies; secondly, specific teachers who have specific issues which need to be addressed.
2. Review the options and choose a course of action.
3. Communicate what is being done and why, and do it.