common sense suggests a near universal attainment like HS diploma (80-something%) might be near the intellect mean. common sense suggests a less universal attainment (38%) would be above the mean.
i think some of you have confused "student" with "graduate." lot of people start, less finish.
there has been a lot of growth in Second Rate State and jucos. you open the doors wider it starts to look more like the rest of us. do i believe it literally mirrors the country? no. HS would. i buy every half cooked juco kid who couldn't pass remedial college algebra and continue might be near average.
do i believe college graduates are average smart? hell no.even the study you cite argues good, selective schools wouldn't be average smarts.
if you think harvard kids are idiots because some study you read came up with an average IQ number for canadian college students, you need college.