Modeling teaching offer database

Question

I’m studying databases and I’ve come up with a problem that I’m not getting out of. The problem is:

"A school conducts education level offerings annually. Each year, one or more levels of education (middle education, middle education) are offered. Each level of teaching can be offered in different shifts (morning, afternoon etc). Each shift has offers of different grades of the level of education (for example, 1st grade of high school can be offered both night and evening; 8th year of elementary school can be offered only night). In addition, each series has different classes. So, prepare a database for the annual offers".

Thinking about this context, I modeled the first tables according to the image below. However, I’m failing to create a logic to model the school’s annual offerings part.

The tables I have created so far are to store the values of levels of teaching, grade, turn and relationships n:n.

If anyone can help me in this logic of how to model the offering part, I would appreciate.

IMAGE:

Answer 1

When observing your model I see some problems as for example:

• From the table 'Class', apparently it is not possible to know which school she belongs to, as well as it is not possible to know in which year a certain class existed. Part of your problem could be solved by having a relationship with the 'Offer' table, but I believe that this is still not the best solution to your problem.

So I took a little time to try to make a basic representation of a modeling (without the presence of attributes) that best fits your problem, I hope you can understand:

And assuming that there will only be the fundamental and middle levels, I think, the three tables at the bottom can become one, because I don’t see the need to have a table to store the levels and contain only 2 records, so the records in the 'School Series' table could contain an attribute that instead of saving an education level id, explicitly inform the level leaving the records as something like this:

Well...I hope you understood what I meant to say to you, and any doubt is just to question.