As JTQ says both the Caravan Club and the Camping & Caravan Club run courses.
Couple of years back when I bought my first twin axle caravan I enrolled on the Caravan Club's one day manouvering course. They also run a two day course which is aimed at people with no caravan experience whilst the one day course is more for those wishing to improve their caravan manouvering skills. Although I had been caravanning for over twenty years I felt a little apprehensive about towing, and more especially reversing, a twin axle. I can thoroughly recommend the course, informative and enjoyable. The Club supply the caravan, you just need the towcar, with towball & electrics plus mirrors. You could both go, might surprise you what you would pick up!