Grade skipping is a form of academic acceleration, often used for academically talented students, that enable the student to skip entirely the curriculum of one or more years of school. Grade skipping allows students to learn at an appropriate level for their cognitive abilities, and is normally seen in schools that group students primarily according to their chronological age, rather than by their individual developmental levels. Grade skipping is usually done when a student is sufficiently advanced in all school subjects, so that they can move forward in all subjects or graduate, rather than in only one or two areas. There are alternatives to grade skipping. Timing and other factors Grade acceleration is easiest to implement through skipping pre-kindergarten into kindergarten or skipping kindergarten into first grade directly. By starting the child ahead, many of the problems associated with grade skipping, such as leaving friends behind or knowledge gaps, are avoided. Other key factors to a successful grade skip include the desire of the student, the receptivity of the receiving teacher, and whether a sibling is in the old or new grade. All these factors have been studied and organized into a survey called The Iowa Acceleration Scale (IAS), which when completed yields a recommendation on whether or not to accelerate an individual student. The IAS also cited four critical situations in which grade skipping is not recommended. These conditions are: If the learner scored less than 115 on an intelligence test; If the learner is moved up into the same grade as an older sibling, which could lead to sibling rivalry; If the learner is currently within the same grade as a sibling; and, If the learner does not want to be grade skipped. Cost-effectiveness Grade skipping is one of the most cost-effective ways of addressing the needs of a profoundly gifted student, as it requires no extra resources and very little more than assigning the child to a different classroom, without the expense of special materials, tutoring, or separate programs. The cost of educating the gifted child in a regular classroom with typical same-age peers is the same as the cost of educating that child in a regular classroom with typical somewhat older students, so using grade skipping is essentially cost-free to the school. Students may benefit financially from grade skipping, as recent research shows that children who skipped a grade earn higher incomes in adulthood than similar