The equivalence of ages with grade levels is a fairly ingrained tradition in American education. If a friend tells you her son is five years old, it’s reasonable to assume that the child is in kindergarten; and if a teenager has just gotten her driver’s license, it’s a safe bet that she’s 16 and a sophomore in high school.
Under a purely competency-based grading system, however, those equivalencies wouldn’t necessarily hold true. Competency-based grading evaluates students holistically on their mastery of concepts, rather than assigning letter or number grades. In a completely competency-based model, grade levels as we know them would be done away with entirely; in each subject, students would progress to new concepts after proving their mastery of the preceding material. In partially competency-based systems, age-based divisions are generally left intact, but students’ “scores” during the academic year reflect proven mastery of material rather than arbitrary letters and numbers, and when a student is weak on a given concept, he or she must put in extra work to attain competence with it rather than simply accepting a poor grade and moving on.
The competency-based system may strike many parents as wholly strange and foreign. While its pure form is still relatively rare, however, modified versions are becoming increasingly common across the United States. At least 40 states have at least one school district implementing some form of the model, according to a 2013 KnowledgeWorks report, and while these districts are still a minority by far, the model’s popularity shows a definite positive trend.
Houston’s several Montessori schools use some features of competency-based grading, with adherence to the model varying by school. The School of the Woods, notably, uses its competency-based mastery system as the sole basis for students’ grades. However, no Houston school has yet gone so far as to prioritize competence over age grouping in determining students’ grade levels.
For an excellent in-depth treatment of competency-based grading in the US today, see this PBS NewsHour feature.