By being demanding enough, even a charter school with "open admissions" can target gifted students, at least the subset willing to a do a lot of homework and accept a rigid curriculum. The article mentions the high rate of attrition at BASIS schools, and it would be more humane to have an entrance exam and not enroll students with little chance of success, but that is not politically correct.
http://educationnext.org/high-scores-at-basis-charter-schools/High Scores at BASIS Charter Schools:
Arizona students outperform Shanghai
By June Kronholz
Education Next
WINTER 2014
Fifteen years after its founding by two economists—an American and a Czech, who fell in love at a seminar on the collapse of the Soviet Union—the BASIS network already roosts in the scholastic stratosphere. The Tucson charter school outscored all 40 countries that administered the 2012 PISA, or Programme for International Student Assessment exams, with a mean math score of 618, 131 points above the U.S. average. Its 10-year-old Scottsdale sister school scored even higher: 51 points above the metropolitan Shanghai area in math and 42 points higher in science.
The Washington Post and U.S. News & World Report, in their latest annual rankings, rate both schools among the five best in the country. BASIS students take an average 10 AP exams each, and in 2013 earned an average score on them of 3.9 out of 5. When I scanned the Tucson school’s bulletin board, I noticed that Princeton, Dartmouth, Brown, Harvard, and Williams all had accepted at least one of the 54 students in the 2013 graduating class, some of them on full scholarships; Stanford accepted four.
Teachers Are Scholars
For all that, BASIS schools are open admission. They operate on a shoestring budget: the Arizona schools operate on about two-thirds of the average funding for a child in a traditional public school. Classes are large: up to 30 students in middle school. Technology is “akin to cuneiform tablets,” Scottsdale’s head of school, Hadley Ruggles, told me.
The BASIS curriculum and its hard-charging teachers go a long way toward explaining the schools’ success. Fifth graders take Latin and can expect 90 minutes a day of homework. Middle schoolers have nine hours a week of biology, chemistry, and physics. Algebra starts in 6th grade; AP calculus is a graduation requirement. The English curriculum separates literature and language, or critical thought; high schoolers take both. There are year-end comprehensives; fail even one and it means repeating the grade.
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BASIS teachers said that they offer slower learners abundant extra help, and that kids rise to meet the schools’ expectations. But at the same time, those expectations may scare off the less-able, less-interested students, which can mean a test-score bump for BASIS. Murphy told me that his class had 120 students when they arrived as 5th graders, but the group has dropped to 40, as youngsters have transferred to schools with bigger sports programs, more social offerings, or an easier course load.
