Schools that implement this kind of alternative are in the minority; parents do not often have this alternative and, with a very gifted child, must choose between skipping or not, unless they have the resources for and can arrange private tutoring. Sometimes there is an older college student relative who could do some formal tutoring. In some schools, the faculty may not be in favor of skipping and in others there can be a disagreement between the school personnel and parents as to whether the child is a good candidate for skipping. Advancing in a class is not necessarily grade skipping. Rather, it is more for people who show a much higher level of intelligence, while the other students are left in the grade-level class. For example, an eighth-grade student who is doing very well in his advanced algebra classes, but finds them too easy for him, may be given an option to take a test, and if he passes the test, he may be moved up to geometry or whatever the next level up mathematically may be while still in eighth grade. His schedule does change, but usually only one class is substituted. Grade skipping allows students to learn at a level appropriate for their cognitive abilities. For the majority of gifted students, grade skipping is beneficial both academically "and" socially. American schools commonly oppose grade skipping, or limit it to one or at the most two grades, regardless of the student's academic and social situation. There is no research that supports these limits, and the decision to limit grade skipping is mostly based on the intuition of school personnel or the administration's lack of knowledge regarding possible academic and social benefits. Refusing to promote the student to an appropriate level can result in social isolation and educational underachievement.