Take it to the school board. Demand a change of teacher. Bureaucrats, fascist ones like the teacher have in common with cockroaches, they hide from the light,
It’s pretty simple.
Parental authority > teacher authority
Parental authority > State authority
File a complaint for child abuse by the school and get a restraining order against the leftist teacher, the principal, and school board, until they crawl to the child with an apology.
Most school board meetings have refreshments, including... wait for it... cookies.
Pick up the tray, tell the board these are an unhealthy choice and how dare they have these on school property, and then leave with the tray.