Baiting the Enemy

You can get in and do this easily with no combat, no deaths, and no stealth required.

There is a dirt ramp up into Proudmoore Keep at 32.89, 52.86 (coordinates taken inside the Boralus map).
At the top of the ramp go up the stairs on the left. A Boralus Civilian sometimes patrols down the stairs.
At the top of the stairs, there is another set of stairs to the right. Jump onto the wall between the two stairs (You might need to go up the second set of stairs a short way to get onto the wall)
Follow the wall around. Beware the Admiral's Elite Guard patrolling around the platform up on your left.
Once around the wall, jump across the railing on the stairs in front of you.
From here you can cast into the pool that spawns at 38, 67. If you have an Anglers Fishing Raft you jump in and fish other pools without leaving the water.
Some pools can be reached by carefully edging around the moat. Note there are elite guards near the steps leading out of the moat so don't jump in without a plan.
Flight Master's Whistle or Hearth out.

One cast into a pool at 40,70 in Proudmoore Keep completed this achievement. Screenshot over here to show my position.

World quest is not needed for the school to spawn, it just has a long respawn timer. I went in Proudmoore Keep on my horde mage and camped the pool for about an hour before it spawned and there was no WQ for the area.

If you dont like to corpse run alot, either do the achievement with stealth class, wait for WQ for clearer streets or wait for flying to be enabled.

Good luck.