You can buy an outlet tester to check weather ground is properly wired (in that outlet).

If you're being zapped by a whiteboard hanging on a wall then most likely it is static electricity generated when you walk across the floor. You didn't specify but I'm guessing the floor is a plastic laminate?

You could put down anti-static floor mats. For example under each desk. This would keep you from building up charge as you move around. Running mats across the entire floor may prove cost prohibitive.

You can buy an outlet tester to check whether ground is properly wired (in that outlet).

If you're being zapped by a whiteboard hanging on a wall, then most likely it is static electricity generated when you walk across the floor. You didn't specify but I'm guessing the floor is a plastic laminate?

You could put down anti-static floor mats. For example under each desk. This would keep you from building up charge as you move around. Running mats across the entire floor may prove cost prohibitive.