I loathed substitute teachers when I was in high school. Most of the subs tried their best, but I liked my teachers and treated their temporary replacements as interlopers. My friends who didn’t like school at all were similarly hard to manage.

I was pleased, then, to see that former school superintendent John Fitzsimons has a plan to eliminate short-term subs from high schools. His recent commentary in Education Week said “hiring substitutes can be an administrative nightmare. Most school districts contract with substitute services that experience frequent turnover. Often, first-time subs arrive late or not at all, and the administration scrambles to find a free teacher to supervise the class.”

When Fitzsimons was superintendent of districts in Tenafly, N.J., and Lawrence, N.Y., he allowed classroom teachers and their students to work out their own plans for handling teacher absences. Many organized their students into study groups that would meet in the cafeteria or library.

“Some teachers arranged for students to audit other classes, work on art projects, practice music or engage in club activities,” Fitzsimons said.

That may be expecting too much. Many teenagers I know, given an unexpected free hour, cannot resist curling up in an empty desk for a nap. But what’s wrong with that? As Fitzsimons points out, most high school students will go to college. They won’t find subs taking a sick professor’s place. They might as well learn now how best to use that time.

Despite my dislike for the subs in high school, I have matured somewhat since and realize that substitutes are admirable people. My mother was one for several years. She taught full-time only when I was in college so that we could afford my room, board and tuition. Many subs are good in the classroom. Also, making some money subbing can keep a family financially afloat in hard times, like now.

The pay is not great. The U.S. average for subs is about $80 a day, maybe $100 a day around here. But it adds up. Arlington County last year spent $618,499 on substitutes for four high schools and programs for that age group. Prince William County spent $1.3 million for subs at its ten high schools. Frederick County, Md., paid for 90,675 hours of high school subbing at $11.49 to $15.91 an hour.

Winchester, Va., with just one high school, spent $153,473 on subs for eighth through 12th grade. Fairfax County spent $19 million for all subs, which I estimate means about $4 million for high schools.

The approximately 200 high schools in the Washington area spend about $30 million a year on substitutes. Some of those are essential long-term subs, but shedding short-term replacements would still save serious money.

Visionaries such as education consultant, blogger and former sub Nancy Flanagan have suggested eliminating subs at all grades. In one Education Week piece, she suggested creating full-time floating teacher slots, or having master teachers, working to improve staff skills, fill in when needed.

Those ideas are interesting, but impractical or impolitic. Frederick County schools spokesman Michael Doerrer predicted trouble finding space for the students of absent teachers. I see a much better chance for changes that give more responsibility to students.

I learned long ago that well-taught classrooms don’t need substitutes when the teacher is absent. Frank Corcoran, an original teacher and now leader of the first KIPP charter school in the South Bronx, panicked when a subway breakdown made him an hour late for a class during the school’s second year. Running up to the classroom door, he expected chaos. Instead, he heard two of his best students calmly conducting the lesson, reminding the inattentive that Mr. Corcoran would not put up with that, and neither would they.

I hear stories like this often from urban teachers who have won their students’ trust and loyalty. Given that this region has a higher percentage of hard-working, well-motivated high school students than any other, why not give them a chance to decide what to do on those days when their teachers can’t make it?