Musuko Ga Osewa Ni Nattemasu!
1. Kindergarten teacher and one of the dads has a one night stand and then get into a relationship 2. Single dad and high school homeroom teacher meet in a grocery store. Dad goes way too overboard chasing teacher 3. Classmates compete to see who gets to be rich kid's butler, but it's just secretly a set up to get two of them together while perverted rich kid gets to watch butler play
Kodomo x Otona no Houteishiki
1. Single dad and the kindergarten teacher that plays mom 2. Son from first couple has a crush on the teacher, but finds out he's dating his father. Instead a childhood friend from the kindergarten comforts him 3. Middle (high?) schooler who wants to be noticed by girls joins the handcraft club, but ends up falling for the only guy in the club.
Sensei wa Butchozura Shite Yatte Kuru