Absences begin to accumulate with the first scheduled class meeting. The Maricopa County Board of Supervisors Formal and Informal meetings are open to the public and will proceed under ARS 38-431 et.al.For classes with published start dates and meeting times, registration in the class must be completed before the first official class meeting date and time. MUSD offers many signature programs across our 11 schools. 9500. Students. MUSD serves 9500 students in Preschool-Grade 12. Registering for college classes in a big step in the next part of your educational journey. Visit our school, located on the SE corner of 11th Avenue and Osborn Road (OSE 105) at Phoenix College. Notice of Public Meetings. Please reach out to the school office to let us know. The public is welcome to attend all meetings!