Passbooks: - National Learning Corporation has been a leading publisher of test-preparation Passbooks(R) for more than 50 years, with 6,000 titles available across 22 series. The Admission Test Series prepares students for entrance examinations into college, graduate and professional school as well as candidates for professional certification and licensure. Each book in the Admission Test Series offers practice through multiple-choice questions and answers in relevant subject areas, as well as informative texts to aid in understanding the study material.