Re: Ignorant Brit here
"Grade Point Average is a calculation from all of your test scores averaged"
GPA was explained in detail in a later comment, but it's actually an average of your marks or grades which include course work such as term essays and even subjective factors (as exploits the plot line of many a movie). Test scores are a wholly different mystery, the most notorious being LSAT, for which the keener may buy textbooks or hire coaches.
Education in Canada is a Provincial responsibility, and I believe that in the USA it belongs to the States. So in North America you have at least 60 educational jurisdictions. And yet, there is a surprising level of consistency. "School" consists of 12 levels called Grades (not to be confused with grades, which are course marks). The simplest division of "school" is "Elementary" (grades 1 to say 8) and "High School" (9 to 12), though there can be variations, for example "Middle School" (5 to 8 maybe), "Junior High School" (8 to 10), "Senior High School" (11-12). "Secondary School" is a synonym for "High School". In USA, High School students are Freshman (Grade 9), Sophomore (10), Junior (11) and Senior (12). Then if they go on to Post-Secondary Education = College = University, the whole nomenclature is repeated: Freshman = 1st year and so on. So persons A and B may be "Sophomores", but differ in age by 4 or more years, you need to know the context. Just as you need to know the context in Britain for say 2nd year at various levels.
In Canada the system is similar. When I was growing up, and it may still be true, we did not use GPA. We also did not use the Freshman ... Senior nomenclature, ever. In some places, schooling was 11 or 13 years, but that's pretty much disappeared except perhaps in Quebec, where after 11, there were two years of CEGEP and only then do students go on to College = University. 40 years ago, old people would talk about "Junior Matriculation" (or "junior matric") and "Senior Matriculation" although perhaps mostly in Ontario, and it had to do with the fact that you could leave school with your head held up high after 11, 12 or 13 years. But later in Ontario, you would take 13 years. Then a further 3 years at College = University would give you an ordinary (Bachelor's) degree, whereas 4 years at University might result in an Honours degree. But where I went, it was 12 + 4 for everybody, and the "Honours" could result only from taking more courses including certain specific ones. So if you wanted an Honours Math (not Maths in Canada) degree, in 3rd and 4th year you'd be learning a lot about Analysis, but if you wanted a vanilla Math degree, you could slack off with Geometry or Number Theory or Modern Algebra. In addition, if you averaged marks (grades) of 80% or more, the degree on your transcript (but not on the diploma) would be marked Class I, whereas 70?-79.99% would be Class II, etc. I bet they've at least tried to make things more standardized in the ensuing decades. In the Real World, a Math degree and a driver's license would go a long way towards qualifying you to be a taxi driver. Hardly anybody gave a flying puck about whether you had an Honours (except grad schools) degree, and nobody at all cared about Class I. On graduating, I purchased a Sealed Transcript of my marks, mindful of future employment opportunities. I still have it, still sealed, over 40 years later!
In USA, a College tends to be a 4-year institution that grants only Bachelor degrees. University would be a College + Masters and PhD's. In Canada, there is a tendency for a College to not even grant degrees. You go to a local College for two years and then possibly to a University to complete the Bachelor's.
Cross-pond Educational confusion extends also to occupations. In one genealogical Family Tree, some of my relatives' occupations were labelled as "Lecturer". To which I joked, I've got you beat, I'm a Haranguer. Deep down I probably knew what they were, but the England-based compiler of the tree relented with "University Lecturer". Here in Canada, that might be called "Assistant Professor" or "Associate Professor". By contrast, there was no confusion about what a "Wine Merchant" was, though we did remain with a mild disagreement about the person who was "Theologian" from one point of view, but "Missionary" from another. Even there, cross-pond differences in norms and expectations played a role.
Please excuse the verbosity.