Courses and course formats

Hello everyone,
Some times the content on the main page is too much and hiding sections do not help very much.

Has any one done any work in the area or creating category within a course so that you can create other activities inside this category?

So l will have a course MATH101
In side this course, l will create a category.
Inside this category, l can create as many activities as possible.
I can also create categories inside this category and other activities inside those subcategories.
The category can be expanded or collapsed.

This makes organizing items on the course page easy.

Hope to hear from you soon.