Obviously, the main thrust of what I said was that it should not, since if it is to be taught the pagan-lite elements such as belief in the power of crystals and horoscopes, lessons would at some point have to dabble in the world of the occult and the 'spirit world'. Or, at least, it would be hard to teach what some pagans might believe about stuff like horoscopes if you didn't also include the stuff the some pagans might believe about trying to contacting the dead.
If paganism were a religion to be taught alongside Christianity, Islam, Hinduism, Judaism and other significant religions, then exactly what would be taught? The problem of course is that paganism would mean something different depending on which pagan you happened to be talking to. For one it would mean visiting Stonehenge at the summer solstice, for another it might just be some kind of meditation, for another casting a spell, for another reading someone's palm and for another, looking at horoscopes to see what the stars have planned for you.
Paganism in the 21st century in Britain doesn't mean what it meant in pre-Christian Britain, but what does it mean. Should it be taught in schools? Well, what is a Catholic Christian meant to say? No, it shouldn't. Already, children leave schools with little knowledge of what Christians believe. Teaching paganism is just another sign that the Christian content of an RE curriculum would be diluted even more. I'm sure most pagans are 'nice people'. I'm sure most British people are pagans because as Chesterton said, 'When people stop believing in God, they don't believe in nothing. They believe in anything'. The question is do we want to build a society in which children believe in anything - literally anything - even the mystical or fantastical world of sorcery, but with little to no knowledge of the Gospels? And, of course, it has to be said that teaching children about paganism does run a risk that children could develop an unhealthy obsession with the occult. Most sensible people in the UK believe that the world of the occult is a door that one could open if one wanted, but that it isn't very wise to open that door. Most people know someone who has known someone who has used a ouija board and regretted it. Is satanism a 'real religion' that could be taught as part of the paganism module for those pagan who actually go in for it? I mean, where does such a venture start and end? You could teach satanism side by side with Christianity but from what I know of education, children's behaviour in schools is bad enough already...
It's an interesting question, I think, how do you teach paganism when it means something different to every pagan? As far as I know there is no pagan pope, though, there may be a lecturer at a Catholic university somewhere who could apply for the position were it to be created.