At our school, we teach the traditional tai chi forms with over 80 moves that take approximately 25 to 30 minutes to perform. We do not teach the shorter forms like the Simplified or 24 Form routine because these forms were created for the purpose of competition to be completed in a very short time. Many are intimidated by the traditional long forms, unsure if they can learn or remember so many moves. This is when a good teaching system can make a difference in your learning experience.
http://www.taichi.ca/mississauga-etobicoke-toronto-ji-hong-tai-chi/tai-chi-taiji-quan-qi-gong-yang-chen-push-hands-weapons-mississauga-school-teaching-system/