Co-ed or Not Co-ed?

This afternoon a student from former Class 306 paid me a visit.   Now a freshman, he found it harder for him than for those who came from co-ed schools to get along with the opposite sex .  During his three years at NHSH, he studied in a single-sex class.  That was the school policy then.  I remember once a student who graduated earlier also told me about the same problem. 

Since about three years ago, NHSH has adopted mixed-sex education, starting with the then freshmen.  Though according to some research I read years ago, single-sex education helps students at the high school level develop better intellectually and mentally, personally, I prefer co-education because it is natural for the two sexes to mix together.