how do you know...

If you have regular periods, you should know the dates it will usually come anyway, so you prepare for it by bringing some pads/tampons to school. If you’re irregular and not sure when it comes, you can usually know the entire week before you get your period because your breasts will be sore, you feel a little tired/cranky, you have cravings, you can feel bloated, and many other things.

Around the time that your period is coming, you might feel that you have a bit more discharge than usual. If your period comes and stains your panties, most of the time you will usually know because you will feel a large-ish amount of liquid discharge, and you will feel a little wet down there like you peed yourself a little.

So when you feel this or think that your period came in the middle of class, excuse yourself and tell the teacher that you need to see the nurse for a “female emergency”, and even a male teacher will get your point without you having to be specific. I’m not sure about your school, because mine never had nurses, but in our toilets there are sanitary pad dispensers that you pay a few cents for 1 pad. If you don’t have those I guess you will have to see the nurse then.

Sometimes it’s also a good idea to ask your close girlfriends if they have any spare pads on them, usually they do.

But yeah, your best bet is to always prepare yourself, and have a pad in your bag at all times or close to the time of your period.