Workout

Warm-up (800)
200 swim
200 kick
200 drill
200 choice

Set (200)
200 kick 

Set (400)
400 pull (buoy and paddles)

Set (400)
4 x 100 pace
...w/10 seconds rest (for a distance swimmer)
or
1 x 50, 2x25  
...w/1:00 rest (for a sprinter)
300 swim moderate

Cool-down (200)
200 choice