Complex sentence: On scholarship, he was one of the first African-Americans to attend the school, Barclay went on to Harvard College, where he was extremely active in student musical theatre productions and the "a cappella" singing group the Harvard Krokodiloes.
Split into simpler sentences: On scholarship, he was one of the first African-Americans to attend the school. Barclay then went on to Harvard College, where he was extremely active in student musical theatre productions and the "a cappella" singing group the Harvard Krokodiloes.