PUBLIC CHARTER schools in the District expel students at a higher rate than do the city’s traditional schools. Are the charters expelling too many, or the school system too few?

The answer is a bit of both; both the charter and traditional schools should examine their policies and practices. Also important is whether the District provides sufficient learning environments for students who struggle in conventional settings.

A recent report by The Post’s Emma Brown showed dramatic disparities between the number of students expelled by public charter schools and the public school system. According to The Post’s analysis of school data, charter schools, which enroll 41 percent of public school students, expelled 676 students in the past three years, compared to 24 for the public school system. The numbers don’t capture practices employed by the traditional system — including long-term suspensions, involuntary transfers or reassignment of out-of-boundary students to their home schools — that essentially result in separation of a student from a school. Also, there is wide variation among charters; a small percentage of charters account for most of the expulsions.

Nonetheless, the charters have a rate that is more than three times the national average; that’s a matter of concern. Scott Pearson, executive director of the D.C. Public Charter School Board, has rightly opened data about discipline to public examination and challenged schools, when their charters come up for review, to change practices. There’s already been an effect (Mr. Pearson reported a 25 to 30 percent drop this year), which argues against a move to put in place ironclad rules of discipline that would tie the hands of charter school officials. Such a move would, in any case, likely violate the federal law that established D.C. charters.

One reason charters have become so popular in the District is parents’ belief that the schools offer a safer and healthier learning environment, with higher expectations about behavior and more rigor in discipline. That raises the issue of whether the public school system needs more flexibility in handling disruptive students. The District’s rate of expulsions is lower than the national average; the fact that only three students were expelled from the system during the 2011-12 school year raises additional questions. Unlike expelled charter school students, who, by right, can enroll in the public school system, those who are expelled from public schools have few options.

The city needs better alternative schools, development of in-house intensive work and more medical residential settings to serve students who are unable to cope with a traditional setting. New Orleans is doing interesting work in this area; it’s something D.C. charters and traditional schools should collaborate on. It’s also time to eliminate the District’s outmoded method of determining school funding based on head count in the fall, which charter critics say provides little incentive to retain troublesome students throughout the year. Money for the education of a child should follow that child.