Hi guys!

Please can you help me out with this ERD - it can be found at this link:
http://namastesuite.co.za/DfP_Productions_ERD.jpg

The company offers music tutoring for vocals, guitar, bass, piano, choir, drums and dancing. The courses do not have set times, levels (intermediate, advanced etc.) - that is all decided once the client is enrolled. This is why I have an Enrollment class, but no Course class.

The system I am designing aims to help financial organization - it allows the manager to confirm that commission payments have been paid to tutors and confirm payments have been received from clients (the system does not link with a bank account though). She currently does this all in Excel and it's tedious.

Our system will also generate a weekly schedule for the tutors to view and update.

Here's a screenshot of the website and the functionality the manager must have http://namastesuite.co.za/screenshotdfp.jpg

My question is: is this ERD comprehensive for the system? I feel like it is very small and think entities might be missing.

Thanks,
Amy