It can feel overwhelming in the beginning. The sense of 'they are trying to do too much with too little' is real. Between teaching classes, rehearsals for assembly shows and conducting workshops, there is a real need to manage your time in the office to get necessary paperwork done.
The onboarding process leaves much to be desired but it is a chicken and egg thing - management does not have the adequate resources to come up with a comprehensive onboarding process.
The temptation to stay after hours is alluring, especially if you're behind on a couple of things - and it can be very easy to fall behind. Therefore, it is vital to manage your time in the office before classes.
Be aware you are joining a small company. It is expected for everyone to wear several hats. If this is something you are not willing to try, this is not the place for you.
At the end of the day, as much as the bosses do listen to you, it is a business. They do prioritize growing their business, but they also listen to the employees as much as they can without risking too much of their business.