40 yrs teaching public HS. Shame on that district in Minnesota. No legal recourse for you?
I worked for most of those years in CA and districts are required to reimburse for those sick days.
I have a buddy who took and AD job at a junior college and his supervisor tried to screw him over. He knew she would fire him at the end of the year and he had over 100 sick days accumulated through the years. He just took the last 100 days off and she had to do his work. Genius!