In 1964, scholars at Yale University began preparing calculus textbooks as part of the work of the School Mathematics Study Group. In the fall of 1964, 12 seniors (8 male, 4 female) at Joel Barlow High School in W. Redding, CT, under the tutelage of Mr. Dobelstein, became one of several (two dozen?) classes across the country to work with these experimental textbooks. The text was distributed in a series of paperback pamphlets with a pastel blue cover. Several texts were provided at the beginning of the school year and the authors wrote the next chapters as the students worked their way through the lessons. Mr. Dobelstein encouraged us to examine the text critically, and we delighted in discovering typos and submitting them back to Yale. At least once, we finished a booklet before the next one was printed and sent to us -- which we cheerfully celebrated. At times, if we finished a lesson on time, Mr. D. would spend the balance of the class time teaching "football appreciation." The young men relished it, but my recollection is that the young women conversed on a topic of more interest. Morale was high; we'd been promised college credit for the class -- groundbreaking for the times.