Education Next – Brian A. Jacob
“Critics of mandatory retention have long argued that it is harmful to children, offering little academic benefit while increasing the likelihood of eventual dropout. And, it is true, compared with peers who have progressed normally through early grades, students who repeat a grade during elementary school tend to have notably worse outcomes. But it is also true that students who are held back tend to face greater challenges for many reasons—they are more likely to come from disadvantaged backgrounds and have lower initial academic achievement relative to other children. Even if two children appear similar in terms of all observable characteristics, it is nearly certain that the retained child differs in some important way from the child who was promoted, and it is likely that this difference will influence each child’s long-term outcomes. In the program evaluation literature, this is known as selection bias, and it makes it very hard to infer the impact of a particular program or policy from observational data.”(more)