by David Safier

At the original campus of BASIS charter school in Tucson, the class of 2012 had 97 students when they were 6th graders. By the time those students were seniors, their numbers had dwindled to 33, a drop of 66%. At BASIS Scottsdale, the second campus opened, its class of 2012 fell from 53 in the 6th grade to 19 in its senior year, a drop of 64%. Those numbers aren’t unusual. Every year at those schools, the number of students dropped between 60% and 71% from 6th to 12th grade, based on the Average Daily Attendance data the schools submitted to the Arizona Department of Education.


BASIS charter schools’ high school students do stunningly well in AP classes and on other data-based measures of student achievement. But not many people understand how the schools arrive at those high numbers. They winnow the weakest students year by year until only the most academically successful survive.

When students begin their schooling at any of Arizona’s BASIS campuses in the 6th grade (recently the schools began accepting 5th graders), they are already
among the highest achieving, most motivated students in the region. Because
of the BASIS reputation, most applicants are strong students — or have parents with high expectations — who apply knowing the school will be difficult academically. By charter school law, everyone who applies has to be accepted unless there are too many students, at which time they will be chosen by lottery, but BASIS does what it can to make sure the students have a reasonable chance of meeting with the school’s high academic expectations before they start school in the fall. When they are accepted, students take a placement test. If they score low, the students and their parents are counseled that the students most likely won’t be successful. If they really want to enter the school, they will be moved back a grade.

But even self-selection and a placement test aren’t enough to assure that students succeed at BASIS. The middle school years — grades 6, 7 and 8 — are the proving grounds. Students are pushed hard academically in those grades, but they know the academic demands will be much tougher when they hit 9th grade. As a result, a large percentage of students withdraw between 6th and 8th grade years, generally 50% or more. The biggest dropoff is from the 8th to the 9th grade, when students who have been barely hanging on decide — or are counseled — to withdraw before they enter high school.

BASIS began its first school outside Arizona this school year, in Washington, DC. The school began in October with 443 students; 43 withdrew in the middle of the year. BASIS kept the money it received for the students — hundreds of thousands of dollars — and the schools that had to admit them mid-year got nothing. Because of high rate of student withdrawal, the DC charter board refused BASIS’ request to raise the number of students it is allowed to enroll next year. Once parents in DC catch on to BASIS’ tough academic standards, fewer of the “wrong” kind of students may enroll in the future, which could mean fewer mid-year withdrawals. But residents should expect each class to get smaller and smaller as students drop out at the end of each year and aren’t replaced.

BASIS has big expansion plans. It wants to open a campus in Texas next year with more to follow, and it’s been selling its academic success nationwide. Communities would be wise to expect most of the students who enroll in middle school won’t make the final cut. They’ll be gone long before high school graduation rolls around.

Below are charts of attendance numbers at BASIS Tucson and BASIS Scottsdale which follow the classes through their senior years. Other BASIS campuses are too new for their attendance numbers to indicate significant trends.

BASIS-Tucson-attendance BASIS-Scottsdale-attendance