It's entertaining. A little bit creepy - not the age gap (which is more like an age void ... ^^), but how the kid copies her mom. And I'd also would have preferred some sort of explanation how the kid knows about the teacher's unrequited love and how/why she's apparently immediately in love with her.
But it's fun enough as it is.
Given the conversation, they reunited at the entrance ceremony and her mom call the teacher "Mina", which is a nickname that came from her given name, and for Japanese, using given is either really rude or really intimate, the teacher also said she still not over her first love, someone who got married and has a child