Full-time classes for the gifted don't raise scores of high-IQ gifted students but have positive effects on other high achievers.
In Does Gifted Education Work? For Which Students? (NBER Working Paper No. 20453), David Card and Laura Giulianoreport that full-time classes set up for gifted students don't raise the achievement of gifted students, but have large positive effects on non-gifted high achievers in those classes - especially on the reading and math scores of low-income high achievers. The authors conclude that establishing "a separate classroom in every school for the top-performing students could significantly boost the performance of [these] students in even the poorest neighborhoods," without harming other students or increasing school budgets.
Using detailed administrative data from one of the largest school districts in the United States, the authors tracked the progress of three distinct groups of students who were eligible for placement in classes for the gifted from 2004 through 2011. District policy required each elementary school to set up a separate gifted class for all students in the fourth or fifth grade who met one of two criteria. So-called "Plan A" gifted students scored at least 130 points on an IQ test. The policy also allows a lower threshold (116 points) for the "Plan B" gifted students - i.e., English-language learners and participants in the free and reduced-price lunch program. Finally, since many schools have relatively few gifted students in a grade, the remaining seats are offered to non-gifted students who scored the highest on the previous year's state-wide achievement tests (known as "high achievers"). Classes for the gifted are the same size as other classes in the district, and students follow the same curriculum and write the same standardized achievement test each spring.
The positive and relatively large effects on the math and reading achievement of the non-gifted high achievers was concentrated among free and reduced-price lunch students and black and Hispanic students. There was also a small positive effect on the writing scores of Plan B gifted students - especially boys and students at schools with high fractions of students who were eligible for free and reduced-price lunches.
The authors note that Plan B gifted students tended to be "underachievers" because their scores on standardized tests were more like those of the high achievers and were low relative to their scores on tests of cognitive ability. They note that it is possible that the program had a negligible impact on the test scores of Plan A gifted students because it is difficult to raise the scores of students who are already performing in the top percentiles. This argument is less compelling for Plan B students whose scores, like those of the high achievers, had ample room for improvement.
Based on interviews with teachers, the authors speculate that many Plan B students may have lacked non-cognitive traits, such as attention-to-task and a willingness to meet social expectations. Such traits may have helped high achievers perform well on standardized tests of routine knowledge despite their lower IQ scores. Differences in these traits may explain why high achievers benefitted more from gifted classes than the Plan B students, and may also explain why Plan B students reported lower satisfaction with the gifted classroom environment than either the Plan A students or the high achievers.
-- Linda Gorman