Build Data Base CRM for our School

Hi, we are looking for our own data base/CRM to be built. We have a Spanish program and teach Spanish classes at many elementary schools around the United States. We have around 150 active school teachers and about 160 elementary schools that we are teaching at and would like a crm that will do what we need and store the information we need. We currently use Excel spreadsheets to run and manage the entire business and have built out podio account to store alot of our information, but we are growing to fast to be managing it this way. We would like our own system something comparable to podio so that we can have 3-5 different main categories and many subcategories inside the main one. Each one of our schools will need to have its own page with their specific class schedule, teacher, contact information for the school, processes for this specific school, and more. Out of the 160 elementary schools, there are about 20 school districts they fall into, each school district also has its own procedures (so they will need their own page) and we need to be able to connect each school with their district and their teachers and the substitute teachers that will do that class. We also need to be able to put notes on the specific school, district, and/or teacher. I'm not sure how to do this or what the best platform is to use but we need to be able to change/update it as needed and make adjustments. Please explain and show examples of something you did like this and what platform did you use