In some ways, it seems odd to be explaining or defending coeducation. Isn’t that the norm? Isn’t the burden on single-gender high schools to be explaining or defending themselves? But in some places in the country, including Washington, D.C., there are almost as many single-sex schools as there are coed schools, particularly when you include Catholic high schools. And many of those schools provide an excellent education. So, if you can get a strong college prep education from both single-gender and coed schools, how do you decide?