Routine, mysterious mass firings. I saw this happen four times in my year and a half there, and each time the firings gutted departments. They treat full-time employees like contractors -- use until not necessary, and then fire immediately.
They started an NC office for the lack of labor laws and the ability to offer non-competitive salaries compared to other locations. They take full advantage of both of those factors.
COO is incredibly petty. Employees have to fight for basic equipment that is necessary to complete their job. Are you an engineer? Don't assume you'll have a second monitor!
IXL tries to fails to cultivate buy-in from it's employees. Some of the lower level management is great, however, it's hard for employees to feel engaged when they are constantly treated poorly. Multiple departments changed their payment basis from salaried to hourly, negatively effecting morale, some people get laptops, less important ones get notebooks, etc.
All of the above is SOP for IXL Learning.