Goldilocks continues to be a popular analogy for a reason. Things are best when they are just right. Astrobiologically speaking, the Earth is a “Goldilocks planet,” in a habitable zone just the right distance from the Sun. A “Goldilocks economy” features moderate growth and low inflation and is just right for the vast majority of people. High schools of between 200 to 500 students are in the Goldilocks zone as far as school populations go. St. Mary’s stays steady at about 160-170 students in the middle school (Grades 5-8) and about 330-340 students in the high school (Grades 9-12). These are great numbers for many reasons. Everybody can get to know each other and every student is known well by several adults on the campus. The student body is small enough to give students many opportunities to assume leadership positions in student government and in the numerous clubs, teams, and academic competitions we offer. On the other side, the student body is large enough to field competitive teams in almost all sports and to avoid the “social stagnation” that can come in very small schools. Exhaustive studies by the Gates Foundation also show that academic accomplishment and college success are much higher in schools of this Goldilocks size. This is precisely why some big high schools started to try offering a “small schools” experience by creating artificial divisions within their big schools. That has not worked out, and the Gates Foundation gave up on funding those efforts. Those schools that tried it are still big, but now they are big and splintered in weird and awkward ways.
On class sizes, the best studies I have seen peg them at 15-23 students. Fewer than 15 students in a room diminishes the interplay between students that enlivens the classroom and helps learning. More than 23 students means the teacher can’t get around the room to help all the kids, and the students can’t participate in class effectively, get a word in edgewise, and get the attention they need. These numbers hold true in the American system where we value differentiated learning, open discussions, lots of questions, and getting to know each student as an individual. Many Chinese classrooms of 50-70 students have high academic achievement, but the culture is completely different. Getting the answer right and mastering the material is almost a matter of life and death in China, or of a life with some human comforts versus a dead-end life of hard work and mere subsistence. Students are motivated by fear, anxiety, competition for scarce resources among 1.4 billion people, pride, Confucian values, Draconian penalties, public accolades and public shaming, and super-demanding parents. This cocktail of fear, tradition, the desire to “win” at school, and negative reinforcement works in getting students to learn math (sometimes), but a typical American kid would last about four minutes in a Chinese classroom. So, at St. Mary’s, our school-wide average of about 18 students per class is in the perfect Goldilocks range for the nice, humane way we teach.
Finally, a single human being can perform only so much work each day. In American manufacturing plants time and motion studies help managers set the speeds of various industrial machinery, which allow the bosses to expect and to predict a reasonable output from workers. For teachers, such time and motion studies have shown that their own performance as teachers, and, more importantly, student achievement, fall off a cliff after a high school teacher has more than 65 students to teach each day. It maxes a teacher out to get to know 65 kids, grade 65 assignments in a timely fashion, and prepare good lessons that engage all 65 students. St. Mary’s teachers, in the Module System, as a schoolwide average, carry a student load of just about 40 students per module. This is an incredibly good number. Public school teacher loads, due to budget cuts, have insidiously crept up to 160 to 200 students. Many teachers have six classes with about 30 students in each class for a 180-student load. It’s humanly impossible, despite the quality and dedication of the best teachers, to teach this many students effectively. It’d be like asking a doctor to see 100 patients a day, take good, personalized care of their health, and maintain accurate and detailed medical records on all of them. We've listed this point last in our Top Ten list, because we’ve seen that parents don’t often care or think about this “student-load” issue. In many, many ways, it could be #1 in this list as it constitutes a huge, positive difference in the student experience at St. Mary’s and accounts for much of the high academic achievement at the school.