A Goal Has Come (2021)

The overall vibes is very similar, the main character narrated throughout the drama. Both drama has a story where teenager dealing with unfortunate events and involved in crimes then regreting what they've done. Both drama also highlights on bullying that can't be seperated when it comes to korean high-school drama.

Both dramas start with main character struggling, involving bully and illegal things, running away from home and finally the character growth.

Here’s my plan may not be as dark as Extracurricular but both dramas are similar in the sense that they are both about teens who live alone and carry out illegal activities to make a living.

The male lead is the same actor and his character is sweet and adorable here as well.
One of them tries to seduce the other and you will be able to feel the spark between them.

Here's My Plan has a similar tough and assertive FL . You don't always approve of the FL's actions in either show but you slowly understand why they are the way they are and keep everyone at a distance. Similar dynamics, but Here's My Plan has more slice of life vibes while IOTNBO has more fantasy/melo vibes.

Both have tough and assertive female leads whose actions you don't always approve of. If you liked the morally gray Jo Yi Seo from Itaewon Class, you'll love the focus on the FL in Here's My Plan.

Here's My Plan has more dark humor while JBL is more soft/melo, but they both have a slice of life feel and show characters dealing with difficult life and family circumstances.

Both dramas have a morally gray lead who manipulates those around them and keeps you guessing about their intentions. Great characters and engaging stories.

I feel Lee Ji An from My Mister and Lee So Hyun from Here's my Plan are very similar characters. Both have a tragic past and consequently go down the wrong path. Both meet new good-natured people who help them.