The percentages of students citing the epistemic strength of explanation (e.g., "It gives a reason") ranged from 30% among the young teens to 60% among the graduate students. The percentages citing the epistemic strength of evidence (e.g., "It's something that really happened") ranged from 11% to 76% across groups. Percentages citing the epistemic weakness of explanation (e.g., "It's only a theory" or "It could be wrong") were even lower, ranging from 00% to 26%, and those citing the epistemic weakness of evidence (e.g., "It doesn't say why") the lowest, ranging from 02% to 10%. (From Kuhn & Felton, 2000).