Violence: One character gets slapped by a parent.

Sex and Nudity: One character draws an uncovered woman's chest for an assignment. It's very crudely drawn, but still there. The art teacher encourages him to draw it, describing the characteristics of the chest. One character is said to have an art fetish and can get weird when he talks about doing art. This is a very minor part of the show, though. Other than that there really isn't anything sexual present in the show.

The last four or so episodes cover nude art and its various meanings, as well as how the symbolism relates to the characters in their lives. In one episode, two characters sit drawing themselves nude, separated by a curtain. None of the more sensitive areas are shown. The characters also draw a nude model for an exam. She is shown in a Barbie-doll-esque fashion, though she is as detailed as you can get with those guidelines (I assume for anatomical realism, not for fanservice).

Theological Themes: One character centers her art around prayer and does pieces from different religions, such as Christianity and Buddhism. I'll also mention one character has an ambiguous gender identity and is either a crossdresser or nonbinary. I'm not really sure. They're also bisexual.

Problematic Themes: In the first couple of episodes, Yatora is shown smoking and drinking with his friends. The first couple episodes have some swearing in them as well. Both things fade into non-existence pretty quickly, as Yatora focuses more on art than partying.

Overall: Blue Period was okay. I was really excited at first, since it was about art, and I've always loved drawing and taking art classes. I just felt like Yatora got too good too fast. I would have liked to see him struggle and progress a little more. Most of the show was about him trying to get into an art school and less about him doing actual art. I did adore Yuka's arc and the symbolism in the final exam, though.

As for the characters, there were a lot. Unfortunately, most of them were really boring. I liked Yuka and Yatora, since they were both fleshed out really well, and I was somewhat interested in the brown haired girl in their prep school. She seemed really interesting towards the end, but she was only a very minor character. Yatora is a very inspiring and determined character with a lot of inner struggles. Yuka is very complex and plucky. Unfortunately, the recurring characters don't have much in the way of personalities, let alone character development. I didn't care about any of them.

The art was fine. I liked the way the eyes were drawn, and most of the characters looked fine. However, some of them came out kinda weird, like Yashida and Kuwana. The opening was catchy and the ending was nice, too.

I'd recommend this one for older preteens and up, due to the non-sexual partial nudity. I think it's probably fine for that age group due to the artistic lens it views it through. I do think its' original TV-14 rating was a bit more accurate than the current PG one, though it falls more in between.