Re: School Notice
No, you may not simply ignore it, because schooling is compulsory. The authorities take swift and determined steps against parents who do not send their children to school.
I suggest you write a registered letter (no phoning, no emails) to the authority which has sent you the notice, explaining that you intend to leave Switzerland in July. You can probably prevent a lot of trouble for yourself by including a sentence:
"Should our plans unexpectedly change, such that we stay in Switzerland after all, I will, of course, report to you immediately." That way, they'll know that you will/would fulfil your legal requirements.