Repeal would have given the green light to gay issues in schools; that would have been a big mistake.
Why? Not because I believe homosexuals are second-class citizens - far from it.
In adult society there have been enormous strides towards acceptance, and rightly so. But "adult" is the key word.
I don't believe, from my experience of teaching thousands of teenagers, that they are ready to discuss such an emotive issue maturely in school. The issue is particularly sensitive for adolescents because it probes the raw wound of their own emerging sexuality, where to be "normal" is often the only sanctuary.
"Normal" sex education is embarrassing enough: throw in homosexuality and class discussions - especially those containing teenage boys - could descend into smutty sniggers.
It would take a brave secondary teacher to "come out" openly in the classroom and it's easy to see why: peer groups lacking in confidence often take refuge in prejudice, and fledgling adults are no exception.
Another reason why I am glad the Lords rejected repeal is that I do not believe our beleaguered profession is ready to be split over yet another side issue.
The performance-related pay debate is still a running sore; next term kicks off with a brand-new system of post-GCSE education: why be side-tracked once more by political controversy?
In Scotland, the results of the Brian Souter-inspired referendum over its equivalent of Section 28 showed the depth of public opposition: 82 per cent of Scots were against repeal. Ironicaly, the new Scottish Parliament showed itself to be more out-of-touch with public opinion than the Lords, which has its roots firmly in the Middle Ages.
It is clear that the public south of the border also opposes repeal. As a secondary teacher with children in the infant and nursery sectors, you swiftly gauge parent opinion and I detect very little enthusiasm for repeal.
Emotive arguments often focus on the fact that Section 28 is "prejudice enshrined in law". I have some sympathy with this view.
Teachers already try to chip away at teenage prejudice on homosexuality. At A level, my colleagues and I constantly try to give students an idea of the stifling intolerance that scarred 1890s writers like Oscar Wilde and AE Housman.
But the fact remains that many teenagers are prejudiced when it comes to homosexuality. The dark days of the adolescent tunnel - when teenagers are deep inside their own secret world of uncertain sexuality - is not the time to try to eradicate that prejudice. Most of them will grow out of it anyway.
Teachers must practise the art of the possible. Teenage attitudes on certain subjects can rarely be changed: they just need the space to grow out of them.
One thinks of Mark Twain famously saying that he had found his father ignorant when he was 14 "but when I got to be 21, I was astonished at how much the old man had learned in seven years".
I'm all in favour of more enlightened attitudes to homosexuality. As an English teacher, I'm glad to acknowledge how many great classics were written by gays.
I just don't believe school is the right place to start that process.
Dr Andrew Cunningham teaches English at Cranleigh independent school in Surrey