I went to school both in the United States and Ukraine and while the United States educational system was way more funded, it was not any better. So what if we have a TV in every classroom? Is watching educational movies a better use of time than getting a lecture from the teacher about it?
Again, I don't see any evidence why funding education more would lead to better outcomes. Is there any evidence of this?
I'm sure schools in better founded areas have better students. This doesn't mean that the funding is the cause, those students also come from wealthier families.
The US also has a lot of under-performing minority groups like African-American and Latino students. So comparing US to Canada directly won't work either. Besides, each state in the US and each province in Canada actually administers public education, no the federal government. This makes it harder to compare.
But anyway, is there any evidence that public education improves the outcomes of people who immigrate into the country? For example, compare someone who immigrates with their parents at 17 or later vs. someone who immigrates at 7 years or younger. Do the younger immigrants have better outcomes?