Re:I don't think it's just that (Score 5, Informative)

That some prominent scientific figure, e.g., Einstein seems to be the favourite poster child, didn't do that well in school either

While Einstein left his secondary school early without qualifications, it was not because of academic slackness. His work in primary school had been excellent. Here his mother writes to her sister:

"Yesterday Albert received his grades, he was again number one, and his report card was brilliant."

He went on to a further education college to obtain the qualifications for university entrance. He got fairly high marks here (top in maths and physics, etc).

Some of the "Eintein did badly at school" reputation comes from the difference in Swiss and German marking systems. Switzerland where Einstein studied used 6 as the best grade and 1 as the worst grade. Germany used 1 as the best and 6 as the worst. In time his results of 5 and 6 (good results in Switzerland) were transposed into the German system, making them seem bad. I'm not sure, but I did hear that Switzerland now uses the German system, thus compounding the problem.