I passed the Certified Lean Management exam last month on my second try and honestly feel like I wasted so much time on my first attempt because I studied the wrong way. The first time I just read through the IASSC body of knowledge and took a few random quizzes I found on Google. Got a 68% and needed a 70 to pass. Super frustrating when you're that close.
For round two I completely changed my approach. I built a 6-week study plan and spent the last two weeks almost exclusively doing a CLM practice test every night, then reviewing every wrong answer. That repetition is what finally made the concepts stick — especially the value stream mapping and waste identification sections, which I kept second-guessing myself on. I probably put in 40+ hours total across both attempts.
The study guide I used broke down the five principles of lean in a way my job training never did. If anyone's starting out, I'd prioritize understanding *why* each principle matters operationally, not just memorizing definitions. Happy to answer questions — wish someone had walked me through this when I started.