Tong: Memories(2016)

This drama doesn't compare, but it carries some faint hints from Blue Spring (2001). There's a desperate need for more raw and scuffed school themed dramas rather than the over-saturated soft boys trying to act tough kind of ones, even the highest rated school themed ones fall under the latter. The school genre in Korean drama is practically dead and had been so for the longest time, with the excessive use of bullying, hierarchy play, school pressure and fluffy kids' romance. Extracurricular (2020) is probably the only exception from the recent 10 years, along with this drama. Unfortunately, it doesn't seem they're planning a sequel for this one after a decade already passed.