Multi-age grouping of students was traditional in the era of the one-room schoolhouse. According to the National Middle School Association, the current age- and grade-based system emerged during the Industrial Revolution, in the interest of efficiency and tighter regulations. Schools have returned to mixed-age grouping in order to provide more educational opportunities for students as well as to address issues of staffing cuts and shrinking student enrolments.
Demands on the Teacher
A mixed-age classroom includes students with a wider range of abilities than a single-grade class. Teachers need specialised training in instructional strategies and in curriculum to teach effectively. Most textbooks are not appropriate for a mixed-age classroom because of their grade-based content. Therefore, teachers must develop materials that meet students' diverse needs. In cases where grouping is introduced to save money, teachers may also face increased class sizes along with the demands of planning for multiple levels.
Addressing Curriculum Standards
Many states' curriculum standards are broken down by grade level. These standards form the basis for standardised testing. Instruction in multigrade classrooms may not adequately address all the learning objectives for each grade level. Students may master all the objectives by the time they move on to the next classroom level, if curriculum is planned carefully, but not in the same sequence as their peers in single-grade environments. This is a particular challenge in subjects that depend on sequential instruction, such as mathematics.
Wide Range of Ability Levels
A wide range of academic abilities in the classroom makes it difficult to plan whole-class instruction. Some students may be ready for multiplication while others work on multi-digit subtraction. There is variation in ability in all classrooms, but it can be more significant in a mixed-age group. Grading can be another challenge in multi-age classrooms because it is not possible or fair to hold all students to the same grading standards, so multiple systems for evaluation may be used.
Potential for Misuse
There are schools that use multi-age or multigrade groupings in a systematic way, for the cognitive and social benefits they offer. However, the majority of schools that use mixed-age groupings do it out of need, according to a study by Dr. Chris Berry of schools in the United Kingdom. When mixed-age grouping is undertaken for cost reduction or to accommodate shrinking enrolment, it is less likely that teachers will be adequately prepared for and supported in this kind of teaching.