Nice cast of young, fresh actors, some of whom nevertheless have several drama appearances under their belts. Also some Idol actors (Nu'est/Wanna One, Victon, ex Momoland, TXT guest appearance).
The cast acted very naturally and worked well together in a story very much aimed at a younger audience, although that's not to say older viewers wouldn't enjoy it (I did ?).
The issue of school bullying was treated / portrayed very lightly in the script. Even if not shown, to say someone is beaten up would entail the victim to at least show bodily pain/discomfort in the absence of facial bruising, in order to convey that storyline.
From the way the bullying was exposed during the course of the story, the character's mental scars due to the experience, were quite OTT. Also, for someone mistreated, to behave so nastily to others without reason, was hypocritical and where the 'pitying' aspect came from was never backed up in the scenes from that time, so it didn't make sense why that person would feel that way about even their supposedly closest friends.
At the same time, in the present day, the bully's perspective about their actions was unusual, but I think true to life.
The supporting romantic side stories were sweet and I especially liked So-hyun and Yoo-shin. There was very little kissing, which considering their character ages and personalities, was a bit odd (it doesn't have to be full-on kisses.... but there were less of any kind, than fingers on a hand).
Noh Jong-hyun is an actor with more experience and I've enjoyed watching him in some favourite dramas; however, he blended in well with the other cast members, which I suppose means they got on well and enjoyed working together.
Hopefully we'll see many of them mature into successful actors with lead roles, in the not too distant future.