My entire life I have known speach to mean the verb that describes the act of speaking in the present tense, while speech to be the verb that is the past tense act of speaking professionally/publicly to a group.
According to google :The correct spelling is speech. “Speach” is an outdated spelling from hundreds of years ago and is now considered a spelling mistake.
Does your family use it that way? Did you go to public school, home schooled?
I could see overworked teachers not noticing, especially if your hand writing is ‘messy’ or just that it’s good enough.
I’m thinking your family has used it that way since forever and taught you that way as well, which I think would be pretty cool.