This booklet is addressed to high school teachers, discussing what many researchers consider the most important year of high school, perhaps the most important year of school so far. Freshman year will set the stage for whether a student graduates and whether he or she will be ready for college. Citing years of study, the Consortium on Chicago School Research advocates that grades and attendance are the two most important issues to be faced during high school, and that the two are closely related. Noting that more than 95 percent of students with a B average or better in their freshman year graduate and have an 80-percent chance of finishing high school with at least a 3.0 GPA, the brief notes that nearly 90 percent of freshmen who miss less than a week of school per semester graduate, and that freshmen who miss more than two weeks of school fail, on average, at least two classes. These findings are irrespective of elementary school performance and 8th-grade test results. For Chicago students who want to graduate from college that B average in high school is what it will take to succeed in college. Teachers are urged to help their students set the stage for future success by: (1) Reaching out to struggling, just-below-average freshmen who miss one or two weeks of school; (2) Prompt and early intervention to each student whose grades and attendance start to slip; (3) Coherent class organization so that students know exactly what they need to do to earn good grades; and (4) Working collaboratively with colleagues to take collective responsibility for the whole school. [For Student Edition, see ED498356. For Parent Edition, see ED498355.]