Welcome to SUPsect – Stand-Up Paddleboarding South Essex Club & Tuition. Stand-up paddle boarding school, tuition, coaching, club and tours in South Essex on the Thames Estuary, based in and around Leigh-on-Sea… We also run SUP lessons at Paper Mill Lock on the River Chelmer near Chelmsford. Learn all you need to know about stand-up paddle boarding in our 2-hour Learn to SUP lesson, then come and join our regular free SUP Club sessions (see our location guide).