This is an interesting exercise. The 'Wobbly Board' is 8 x 4 feet plyboard with a bar across the middle on the underside. The board rocks over this bar as you walk across it. Start without the bar, then add a small one. Horses soon become used to the slight movement and noise. Excellent for teaching your horse to go across bridges - Le Trec competitions perhaps - and it helps introduce the principles of loading too.