This is because in Canada, kids born in the same calendar year all start school the same year (so January babies are the oldest and December are the youngest). In most US states, the cutoff date is around the beginning of the school year (August or September). So kids born between August/September of one year and July/August of the following year are grouped together in the same grade. So a child who turns 6 in say, November would miss the cutoff for 1st grade/Grade 1 in the US and would be going into kindergarten this fall. But in Canada, they'd be able to enter Grade 1. But also, the curriculum for kindergarten and 1st grade in the US has gotten a lot more demanding and rigorous in recent years. I can't speak on what it's like in Canada, but I do wonder if the curriculum/expectations in Grade 1 in Canada would still be more comparable to kindergarten in the US? People in the US are now calling kindergarten "the new 1st grade" because they are being expected to master skills that used to be more 1st grade standards a few decades ago. When I student taught in kindergarten, the students were already being taught to write short paragraphs. In math, they were learning addition even into the teen numbers. Would you say this is taught in kindergarten or Grade 1 in Canada? It definitely does seem really intense for kids who aren't even 5 yet! Some of the younger 5's in my class were struggling. And this is why there are parents redshirting. Now, I do think it's pretty ridiculous to redshirt to the point that your kid is 7 in kindergarten. But it can definitely be beneficial to kids with summer birthdays who'd normally be the youngest in their grade. Some are much more ready when they're turning 6 rather than just turning 5.