Great strain for concentrating! I am not a Math whiz, never have been. I am retaking a Stats class that I failed miserably last year and just started smoking regularly this year. This strain has helped me mentally relax enough to be able to focus on the subject matter yet doesn't make me feel couch-locked. I rated it a 4 star only because it takes at least double what I normally smoke to reach this effect. Overall this will be my go-to strain for focus and productivity.