Students will be required to start school at age 4 and continue through age 18, when they are considered adults and able to make their own decisions and live independently.

Nicholson Baker, the author of Substitute: Going to School With a Thousand Kids

The reality is that schools go by age, even when they claim they're embracing "performance-based" as opposed to "age-based" instruction: It just looks strange and embarrassing when one student is two feet taller than his classmates.

Everyone understands letter grades, and the fear of failure is a motivator. Some informal tracking is inevitable. But there's too much ranking and GPA-ing now—it makes the kids who are struggling miserable.

Carol Burris, the executive director of the Network for Public Education

A synthesis of the research on multi-age and multi-grade classrooms (classrooms in which one teacher or group of teachers instruct students of two or more grade levels at one time) shows neither a positive nor a negative effect for this practice. Like block scheduling, a school may embrace the practice for philosophical or practical reasons, but there will likely not be learning or non-cognitive gains or losses for students.

Ability grouping, on the other hand, will be avoided. The research is clear: Ability grouping harms lower achievers while providing no academic benefit for average or higher achievers. Although there are some studies that show ability grouping slightly depresses the learning of higher achievers, the preponderance of studies across decades shows that higher-achieving students are not harmed by being in classrooms with lower achievers.

For 15 years, I worked with my faculty to eliminate ability grouping from our high school and provide all students access to our best curriculum—the International Baccalaureate. Not only did lower achievers benefit, but higher achievers did as well. Mixed-ability classrooms, with a teacher skilled in differentiating instruction teaching an enriched curriculum, is the best possible way to group students.

Catherine Cushinberry, the executive director of Parents for Public Schools

Students will be grouped by age. Grades will be used as a measure of progress for parents and caregivers, and for students ages 13-18—particularly because college-admission requirements may not shift with the change in the school structure. Having age categories for classes will continue to give students something to aspire to as they matriculate. Students will be required to attend school as early as 3 years old. Pre-K students will not be “in class” all day. They need time to play and nap, but will stay in school for the full day.

Michael Horn, the co-founder of the Clayton Christensen Institute

Students will learn in competency-based environments in which they make progress based on their mastery of knowledge and skills, not based on time. The traditional notions of grades will fall away as a result.