I’m USA born, have lived here my entire life, and have known what “being in a tizzy” meant since… 4th or 5th grade? I thought it was a relatively common word/phrase. I do read books though, but nothing fancy. Our literacy standards are apparently spiraling downward.

Same here. Idk about specific grades, but pretty sure everyone knows what tizzy is.

I just remember telling teachers to not be in such a tizzy when I was quite young, certainly before middle school. Generally their state was my fault; I was far from a model student.