The most helpful resource that I found was the Google Training Center site found here: http://www.google.com/edu/training/. I completed the basic training and took the basic exam. No problem. We've been using Google Apps at school for a little over a year so I knew the basics pretty well. Then, it was on to the Advanced Level. This is the level upon which certification is based. I had to pass exams (with at least an 80%) on Docs & Drive, Calendar, Sites, Gmail, and one elective which, in my case, was Chrome Web Browser (because I thought it was the most useful for me).
Each exam is $15 to purchase, so the entire outlay was $75. I took my time going through the materials for each exam, starting with Calendar. It took about a day and a half to read through the materials and prepare to test. After taking the test, and passing (phew), I moved on to Docs & Drive. Same process. Then, on to Sites, Gmail and Chrome Web Browser. The time investment for each exam was different based on the apps with which I had the most experience. We use Docs & Drive all of the time at school so it took less time for me to master that one. Calendar, on the other hand, took longer. All in all, about 9-10 days was what it took for me to go through the site and master the material. The results of the tests are instantaneous. Click the "Finish" button and your score pops up. It is a nerve-racking two seconds :)
When you've passed all of the tests, you get one of these certificates:
I feel a great sense of accomplishment. The week and a half of immersion into the Google Apps will pay big dividends for myself and my students. The biggest surprise for me was Google Calendar. I had no idea that I could do so much with Calendar and use it for so many things in class. If you undertake the certification process, you'll see what I mean. One of the great things about learning all of the nuances of Google Apps is that I can take seemingly unrelated things from one App and apply them in unique ways to solve challenges in class. A little creativity and a little knowledge makes me a little dangerous! Uh oh, look out!