Why can a "High Ability" split grade class maintain a lower class size?

The average class size across BCSC for high ability 2/3 classrooms is 20. The range for these classes is 19 through 27. The average class size for 4/5 is 24, and the range is 19 to 28. Both the averages (around 22 or 23) and the ranges (from 17 to 28) are consistent with BCSC averages in "regular" classrooms. (Primary classes for both HA and "regular" tend to be smaller than intermediate.) In other words, statistically, the high ability classes are generally the same size as other classrooms. The writer of this comment may be more familiar with a smaller HA class, having only 19 students, in his or her school; however, other parents may be more familiar with a larger HA class, having 27 or 28 students. BCSC's offering of HA classrooms has little or no bearing on the class sizes throughout the district.