In reply to Boulderdash86:
I was advised by terra nova some time ago not to do this as it doesn't do any favours for the waterproofing of the tent. I've seen people do this for high altitude trips but a) it doesn't rain, it snows and b) tents are seen as disposable items.
For a DofE group, longevity is a factor and so protecting the tents becomes important. I'd suggest some cool little flags that you can stake into the ground and double them up as pegs for the guy lines. That way, you can take one everywhere for a victory photo too and send them back to sponsors.