Timetable All classes are held at Immortal Martial Arts gym in Seacroft.Our flexible subscription options make fitting Ninja School into your schedule easy, without you having to commit to the same session each week. Sign Up Timetable PDF Monday 16:00 - 17:15 Ages 5 – 14. SATURDAY 09:00 - 10:15 Ages 5 – 7. SATURDAY 10:00 - 11:30 Ages 8 – 14.