The Yale-New Haven Teachers Institute (YNHTI) is an educational partnership between Yale University and the New Haven Public Schools designed to strengthen teaching and learning in local schools. Produced by teachers participating in Institute seminars since 1978, the 100+ volumes containing the teaching units offer many ideas and procedures for teaching English, history, social studies, the languages, the arts, mathematics, and science in elementary, middle, and high schools. From the YNHTI home page, search for units or guides; a full list appears in the Directory of Volumes page. Mathematics curriculum units range from Integrating Mathematical Concepts in the Study of the Atmosphere to A Chronological History of Pi with Developmental Activities in Problem Solving to Practicing Precision: Lessons from Mathematical Language and Writing. Statistics curriculum units range from Paper Airplanes to Scaling the Natural World Using Dimensional Analysis. Each unit includes a guide (synopsis and recommendations), introduction, some lesson plans or sample problems, and bibliographies.