The amount of "growth" varied from student to student, from college to college, and from test area to test area, but the over-all gain was particularly significant in view of the high plateau from which it was achieved. (The sophomore mean scores of the Scholars and Comparisons, it will be recalled, were substantially higher than the scores of a representative body of college seniors.) The fact that the Scholars showed substantially more growth than the Comparison students in the natural science field may be due in large measure to the fact that a larger proportion of Scholars than Comparisons majored in this field.

Several plausible explanations for the Scholars' consistent academic superiority over their Comparison students have been suggested, and there may be others. The first is that the Scholars have perhaps been more strongly motivated than the Comparison students and in many cases have had the additional incentive of wishing to keep their Fund scholarships. (Although some institutions were able to match their Scholars to Comparison students who were also on scholarship, this was not possible in all cases.)

Another is that aptitude scores, according to such limited research as has been accomplished to date, have a tendency to increase somewhat with age among students at this level. In other