I don't know what will happen

няяяя

how many days?
Depending on how many u could get summer school, expelled, or nothing

It says 7 unexcused absents

THATS FINE

But why send a letter?

Because schools get grumpy and start dobbing on people if they think they aren't getting their way

Look at your school's policy list maybe?
Every school is different so ask the internet and you'll get either nothing or shit answers.

That's a lesson from your school : don't miss it.

You will probably be destroyed by your parents (and I hope for you they care enough to do that), whereas I don't think you will be expelled or even be punished by your school.

Check all the same your school's rules and local legislation.

As of now, attend any class, and try to do well without getting negatively noticed.

Ok thanks I'll take that to the heart

The same thing happened to me last semester. You might have to talk to the dean of admissions but for the most part it should be fine. Just try to show up more (believe me I know its easier said than done). Also, try to make sure your absences are excused if you have to miss a day or leave early.

How far into the School year are you?
Depending on whether it was all at once, or not and late in the school year could have some say in it.
If it was all at once, and it was in first semester and you are in third semester, you might just be going through a delayed process. If this is the case, I doubt there is much you can do about any punishment from the school.

>>12 Punishment is a childish problem. When you miss school, the most dramatic is that you lack lessons and training. So, you have to catch everything up, which might be longer and particularly less effective than actually attending the class.

Also, any school stuff can be useful in exams or years later at University (eg, I'm a 2nd year of engineering student, and I've just solved a Pythagoras and Thales problem while working on a compressor).

So anything you miss could result in a deficiency, while anything you specially goodly remember is an advantage.