If you're looking for manga similar to Kodomo no Jikan, you might like these titles.
Senior high schooler Hikaru Umino is desperately in love with his teacher, Kuniaki Shima. When he hears a rumor that Shima is engaged to be married, Hikaru does the unthinkable and forces himself on his teacher. Shima makes him atone for his sin by, unexpectedly, becoming “make-believe” lovers until Hikaru graduates high school. When the time limit expires, can Hikaru let go of his beloved teacher?
Takayama, a teacher living his teacher's life "going on with the flow", is being scolded for his lazy attitude by Fuyuno, the most talented female student in his grade. In fact, Fuyuno has special feelings for Takayama...? Can the forbidden love between a teacher and a female student be avoided?
A 41-year-old teacher and a 14-year-old middle schooler. What would happen if his student, young enough to be his daughter, were possessed by his deceased wife...?
Wataru, a lazy high school student, is visited by the earnest and slightly airheaded teacher, Runa-sensei. So that Wataru can become a respectable adult, she gently starts giving him naughty private lessons.
Toudou Rinko is a serious and reliable class representative, now in 2nd year of high school. It happens that the first male person she starts to notice is her homeroom teacher, Saku Makoto. She ends up helping the nonchalant and playful teacher with his "Love Guidance Room".
Yoshino Haruka, 16-years-old, substitutes for her sister at an arranged meeting and ends up falling in love with Kunihiro-san... To discover the day after that he is her new home room teacher! How are the two of them going to deal with this forbidden relationship?
Yatsugi Chihaya is an innocent high school girl who tries to express her love for her math teacher at a school called Yasaka-sensei by taking a reference from the Manga Porno about the Forbidden Relationship between Teacher and Student given by her close friend Chihaya. Will the Chihaya's feelings be conveyed to the teacher?
Takashi Kobayashi realizes that the actor starring in a guy-on-guy video he watched by mistake looks a lot like his high school biology teacher, Mr. Shintani. The students call him "Mr. Death" because he's a widower, but he never takes his wedding band off. "You're always staring." Mr. Shintani unexpectedly looks back at Takashi, whose gaze had been burning a hole in him. And, after that day, the boundaries between them start to get blurry.