Possible Clues:

• Train group of dolphins
• Train swimmers in group
• Educate child about toilets outside
• Pod formed by like-minded artists?
• Teach swimming group?
• Educational facility
• Troop train
• Drill, for starters, for a number of sides today
• One of those with lots of Oscars, the fishy type, in St Trinian's, for instance?
• Second check by John, reversing coach