One manga similar to Secret Class could be 'Love Parameter'. It has a similar theme of forbidden romance and secret relationships.
You might like 'Mysterious Love Affairs'. It shares the element of mystery and hidden emotions like in Secret Class. Also, the character dynamics are somewhat comparable.
I'd recommend 'Hidden Hearts'. It has a similar tone and explores complex romantic scenarios similar to those in Secret Class. The art style is also appealing and adds to the charm.
Chapter 74 is the strongest chapter-level answer because it starts from Having seen Jiang Li's ID before, he knew that this person named Shiguang... and follows through on The man's phoenix eyes narrowed slightly, he looked at the girl sitting....
If you want the clearest chapter reference, go to Chapter 104. Early on, Zhao Lang let out a light chuckle, "Young Master Jiang, don't be nervous,...; later, the chapter leans on You're Daddy's guests, how could I possibly come to settle scores with....
The best chapter pointer here is Chapter 125, "The Great Seed Selection Contest!". It opens with Next, it was Qi Tianyu's turn. and closes on He deliberately chose the most inconspicuous wheat seeds..
Chapter 77 is the strongest chapter-level answer because it starts from Wen Jiaojiao's reminder calmed Shu Yan down. and follows through on But who knew that the next second, the lottery box would be handed over to....
The best chapter pointer here is Chapter 82, "Jiang Yan and the Chicken Go Viral!". It opens with Jiang Li gave her a fleeting glance. and closes on And so, aside from Wen Jiaojiao, the remaining five set off, each....
If you want the clearest chapter reference, go to Chapter 93. Early on, Jiang Li looked back and saw several aunties linking arms, walking up the...; later, the chapter leans on The leader was indeed the aunt to whom she had read fortunes this morning..
Chapter 87 is the strongest chapter-level answer because it starts from Luckily, at that time, Jiang Li had already taken her pot of stinky... and follows through on I'm driven crazy by him every day.] [+1 from above!.
The best chapter pointer here is Chapter 89, "Brother He, how can you be so unreasonable too?!". It opens with Director Sun took a step back, "What's the rush? and closes on If anyone should be mocking her, it should be me.] Wen Jiaojiao stood to....
A practical answer is Chapter 113, because it turns the idea into a concrete scene. The chapter opens with The next day, Jiang Lili was up before dawn as usual., adds pressure through Okay, keep them steady;
If you want the clearest chapter reference, go to Chapter 130. Early on, This task, the first one, should have been his in the bag.; later, the chapter leans on However, just as he was about to get out of the water and take a short....