First I've heard of that @.@ what a horrible tradition.
When I was a child we didn't regularly "celebrate" St Patrick's Day at school. Those of us with an irish background or an interest in it would dress up in green and orange, but it wasn't a thing where the whole class/school did it. By the time I was in high school it had become more of a "thing" (we also celebrated all kinds of other cultural events, at least one per week minimum). It was still optional though. We had permission to wear green and orange in all kinds of crazy ways, so long as the uniform was still worn and visible. As it was a bottle green uniform anyway, many girls didn't accessorise any extra green. Their loss!
- - - Post Merge - - -
DO NOT BLAME POTATOES FOR THE BLIGHT!! That's like blaming the fleas for spreading the bubonic plague in the dark ages. It was a devasting, but natural, consequence of human actions and practices.
NOTE : for anyone who doesn't know about the Potato Famine of Ireland, it is an unbelievably sad and sickening thing to read up on. Whilst I highly recommend learning more about our history (and this event directly led to the mass immigration that helped develop the US and Australia into the countries they are today), the records, accounts, and photographs are detailed and frequently graphic. Please use your judgement when looking this up.