"Aren't we forgetting the true meaning of Christmas?" Bart Simpson once asked. "You know ... the birth of Santa?"
Any atheist teachers expected to partake in Nativity plays, sing overly religious Christmas carol lyrics and field pupils' awkward questions about Jesus can perhaps take solace in the fact that, for most kids, it's all about the fat man in the red suit with the bulging sack. Is he bringing an Xbox and Call of Duty? How about a Go Go Hamster and a Twilight make-up set?
The advent calendar is about chocolate and excitement, not religious symbolism; the Nativity play is a thrilling chance to act in front of the whole school while resourcefully destroying your family's best tea-towel. Eyebrow-raising lyrics like "Cast out our sin and enter inBe born in us today" will be cheerily sung by children, yet wash over their heads, much like "Oh my God!" (as an exclamation of surprisehorrorexasperation) and "Bless you" (in response to a sneeze).
Christmas in Britain, then, is generally as secular as The Muppet Christmas Carol. But what if you're an atheist working in a Christian faith school, or an inclusive school with an overwhelmingly religious staff that goes in for "Jesus is our saviour" assemblies? What if you're expected to teach children things that simply contravene scientific evidence?
The answer is: leave out the "sin and salvation" stuff, give them the facts, and let them choose what to believe. Even the most devout "reason for the season"-loving headteacher won't be able to take you to task for providing information based on truth.
For instance, the Christmas story, dubbed The Greatest Story Ever Told (probably by people who haven't seen Pan's Labyrinth) is just that: a story, much like The Very Hungry Caterpillar or Northern Lights.
It's a lovely tale, but we know that it couldn't have happened at this time of year. Why? Because shepherds didn't graze their flocks in mid-December - the weather then is way too cold for sheep, even in the Middle East. The idea of wise men following a star is also very exciting, but when leading astronomer Phil Plait tried to find the exact star they saw, he couldn't - because it didn't exist. You could even get pupils to read aloud Plait's suitable-for-all-ages account of his search (featured in The Atheist's Guide to Christmas) and bring a rare dash of astronomy into the classroom.
So why do we celebrate Christmas on December 25? Well, because the winter solstice used to fall on that date in the old calendar - this was the shortest day of the year for people living in the high latitudes - and Britain used to observe a Roman festival then called Saturnalia (hey presto, you're teaching them history and geography). Tell pupils that Saturnalia was great fun: as the Roman writer Lucian noted, during this festival, "Everything serious is forbidden: no business is allowed. Drinking, noise, games ... appointing of kings and feasting ... singing ... from time to time ducking of corked faces in icy water - these are the occasions I preside over."
Christians then appropriated that date, declared it Jesus's birthday, and turned Saturnalia into Christmas. Highlight that Christmas is a time for having fun, whether you believe in a religion or not.
You can also explain that a lot of Christmas rituals have their roots in paganism (falling under the lesson topic "classical civilisation"). "The Twelve Days of Christmas", with its repeated line about that partridge in the pear tree, comes from a Scandinavian pagan winter festival, when a giant log - called the yule log - was burnt for a full festive 12 days, to symbolise the sun returning and the days growing longer.
We get holly and mistletoe from the druids, a group of educated priests active in ancient France (Gaul) who believed they were sacred. And the only famous secular carol, "Deck the Halls with Boughs of Holly" (which you can teach them to play in a Christmas music lesson), is all about the yule, making merry and decorating your home with festive plants.
When talking about the Christian elements of Christmas, you don't have to present them as fact. Just prefix them with the words "Christians believe that ...", which is both true and fair, and explain that Jews, Muslims and Hindus also have their own winter festivals in the form of Hanukkah, Eid and Diwali. Many of these festivals are about light and candles, providing celebration, cheer and hope on the darkest days of the year.
And, lest you be dubbed a dry empiricistrationalistsecularist trying to wring all the magic from Christmas, you have three comebacks. First, you've merely taught your pupils about the richness and diversity of British Christmas traditions and the way they stem from our ancestors and draw on a wide range of influences from around the ancient world, while also teaching them about astronomy, history, geography, classical civilisation, storytelling and music. It's a more informative, scientific and all-encompassing approach than usual, but surely that's a good thing?
Second, you can still teach kids about kindness and humanity while telling them the truth. Have an art session in which pupils make Christmas cards for their families and friends, then ask them to list the reasons why they appreciate them enough to draw them a Christmas card. Tell kids that Christmas is about spending time with loved ones and finding ways to thank them for all they do for you throughout the year, giving tokens of your affection in the form of cards and gifts, and sharing the days with them.
Third, you can totally mention the beardy bloke in the sky. Santa might not promise heaven and everlasting life, but he never floats the idea of hell either (unless it's the hell of not getting the present you wanted). He's all about giving and not receiving, is always jolly and cheery, even in freezing weather, and puts in lots of work for the simple reward of making people happy. And if that's not what Christmas is about, then what is?
Ariane Sherine, Editor of 'The Atheist's Guide to Christmas' and founder of the Atheist Bus Campaign.