I found it easiest not to suffer through the boring 1980s-style graphics and dull questions (read aloud, if you wish, by a horribly bored voice-over actor probably wishing she could take a class to start a new career). Instead, I just kept taking the tests, focusing on the parts I did the worst on. (Okay, I had to take a couple parts of the grammar test a couple times. But seriously, the level of obscurity of some of this stuff was ridiculous. You try: Please identify how many verbs in this paragraph are in the past progressive case. Your answer is wrong too.)
Eventually, though, I was able to game the system. The courses I took (which also included ones on InDesign and a class about something called "Six Sigma") seemed to have two sets of questions for each section of the test, so taking the test three times guaranteed familiar questions. Couple that with the facts that 1) the test shows you the correct answer for each question before moving on, and 2) you can take the test as many times as you like with no penalty, and you're on Easy Street.
Paying decent attention while taking and retaking the test (multiple-choice questions, with more than one answer allowed at times) allowed me to "pass" a good number of courses without ever enduring a single "lecture" session. It took a lot less time, too.
However, I wouldn't consider myself proficient in InDesign as a result; the test only taught me about three things, none of which is particularly useful. (The most practical item on the test was how to insert a new layer into a document, rename it, and make it the bottom layer.)
And of course I played the averages; in the Six Sigma class, I lucked out and scored well on certain parts of the test just by reading carefully and guessing. When choosing which portions of the test to retake, I skipped the things I bombed completely and homed in on the topics I had a fighting chance at passing. The system looks for an overall average, and you pass or fail based on that.
That's an obvious flaw, because I passed the introductory Six Sigma class without knowing what a "kaizen event" is, or even, quite frankly, getting a clear explanation of what Six Sigma is in the first place.
Still, if your boss suggests you learn something, check out the course list at smccme.edu/continuingstudies. If there's something there that could help, maybe your employer will shell out the $99 for you to learn. The system remembers your progress, and you can even print a certificate of completion to prove the company's money was well spent.