This location can be reached in the school level, the first level of the game.
Immediately after dropping down from the vent at the beginning of the level, you'll find yourself in the school's first floor hallway. The hallway you're looking for can usually
be found going in the opposite direction of the red wires. Follow the hallways until you see another hallway with some benches in it off to your right. It'll usually looks like this:
** In the event that your hallway doesn't look like this, the room you're looking for is the gymnasium, which will always be located on the first floor.
Walk through the hallway and open the doors at the end. Approach the tree with the swing and the achievement will pop.
NOTE: According to zombizero in the comments, "the achievements do not unlock unless you accept the terms of the app" at the start of the game.
EDIT: I tried this on a dummy account and it's true, so make sure to accept the Terms & Conditions at the start of the game.