Can I hide a menu option from displaying when I set up my

Can I hide a menu option from displaying when I set up my access levels?

I am doing a school website whereas parents can login to view certain content that the general public cannot. For example, Under the menu option called, "parents" a visitor could only see one option in the drop down, but a logged in parent would see a long list of menu items: calendar, photos, etc.

OR a parent would see a menu option in the main menu, or in the sidebar that a visitor cannot.

How do I achieve this?