So this is my first review after watching 40+ anime but I guess I've got to start somewhere.
Green Green is probably the most cliche, poorly animated, poorly voiced, poorly scripted (admittedly I watched it in English dub) but one of the most enjoyable anime's I have seen in a long time. In other words its so bad its good(ish) and I probably only enjoyed it because I just went through a spell of anime's with serious & depressing story lines...
The basis of the story is that a boarding school in the middle of no-where which was (& still is technically) an all boys school recently thought of combining with another school & becoming co-ed; as a result a group of girls come to stay & study there for a month as a trial-run. No points for originality but its fair enough for a echi harem romance right?
Oh and there's some forbidden love thing going on but you needn't care about that (seriously its the most awfully executed thing in existence)
The issue is that for these to work you need to at-least have to have 1 of two good things (preferably both) 1) depth to the characters 2) Enough detail in the character design and enough fan-service for people not to care about the characters... though even then it can be very distasteful...
Green Green unfortunately has neither... The characters personalities are as bland as their design (I think water might have more flavour). There is little-no character development and even the main protagonist only gets a minor back story... and minor efforts in his design.
The only saving grace for this anime is that whilst the main plot is sooo easy to predict that you'll eat your shoe if you don't get it right, there are 3 support characters (the main protagonists best friends) that save the day with unpredictable but sometimes cliché antiques (but be warned some of them will scar your eyes for life and everyone of them can only be described as cringe worthy).
Overall this anime is almost a cliché abomination with almost no effort put into it; however if you want something to drop a bomb on a pile of deep deep emotions from anime that are weighing you down, simply want something with a lighter tone, or want an anime that can easily make another one look good then this might just be worth a watch.