- better prepared students
As mentioned previously, reintroduction of provincial examinations may have made K-12 schooling more accountable and therefore produce graduates who are better prepared for university. Furthermore, the emergence of new communication technologies (computers, Internet, email) may have facilitated learning and student productivity leading to better (earned) grades
- better prepared instructors
50 years of college staff development may have resulted in better standards of teaching. Indeed, many Ph.D. programs now mandate a course in instruction (though of course a single course only goes so far....)
- better assessment practices
More authentic assessments have slowly made their way into post-secondary education as formal assessment training for faculty has slowly improved.
- changes in grading scales
Many comparisons over time fail to take into account that the grades being compared are from different scales, as grading scales have changed over time and vary from institution to institution (of which more in a moment).