As someone who is fairly experienced with most of the tools in Google for Education, completing the certification course was a low investment of time that helped me learn tips and tricks I had not discovered on my own. The Fundamentals course consists of 13 units that typically include three to five lessons and "Unit Test" at the end. The lessons include text, visual, and video content, and have several quiz questions in a "Lesson Check." Rather than completing each lesson, I used the Lesson Checks to test my knowledge, then reviewed the lessons as needed to fill in gaps. After completing the Lesson Checks for each unit, I took the Unit Tests. The great thing about both assessment tools is that they offered immediate feedback.
While the Fundamentals course was structured to allow experienced Google for Education users to move through quickly, the content was also robust enough to provide support for novice users. The biggest challenge will be making the time available to experience all available content. The format is user-friendly, and lesson format provides natural stopping points where users will be able to save their progress and return later.
After completing the free course (I presume it is an included benefit of my district's Google for Education access), all that was left was to register for the exam. Registration was easy and economical ($10), but may require up to 48 hours of waiting to receive the information needed to complete the exam. I can't give you any additional details, because certification requires committing to a Non-Disclosure Agreement. Just trust me when I state it was thorough.
If you decide to take Google for Education certification plunge, I wish you all the best!