"We can shift around the stars, shut down the world, take the ends of time and tie them together. We just need to steal it and we can change whatever we want." --G. A.

Don't look below if you want to figure it out yourself.
-
-
-
-
-
-
Hints:

Anything to the lower left of the shelf?
Anything near the calendar?
Anything next to the computer?
What about the drawer knobs? And the little keyhole?

Walkthrough:

Grab the hook under the desk. Go to the computer (click it) and get the screwdriver at left. Note the code on the computer, and the -1111 underneath it. 10736-1111 = 9625. Get the blue key from the corner of the calendar. The code when calculated is 134. Go to the closet and get the book. At the shelf, go to the bottom right to pick up the hairdryer. Use the hook on the top level of the shelf to get the green capsule. Place the book in the shelf and pull the lever, revealing a panel. Use the screwdriver on the panel. Press the button to get the orb. Go back to the shelf and use the hairdryer on the paper, note the pattern. Then go to the outlet and use the screwdriver, get the green key. Also see that it shows to multiply the code from the calendar by 123. 134 x 123 = 16482. Go to the desk with the drawers and click the knobs to light them up in the same pattern as on the paper. Then use the blue key on the little keyhole. Enter the code from the computer, 9625, and get the purple capsule. Put both capsules in the box in the closet. A lever will appear, pull it. Leave the closet and turn right, revealing a secret door. Use the green key, enter, and place the orb on the pedestal. Enter the code from the calendar and outlet, 16482. The orb will transform into a gold key. Use the key on the door in the room to escape. The end.

-Kyjast