Why is Takatoshi Tsuda still in second year? I read till chapter 190 and I noticed that in the manga, many sesones passed. Then doesn't that mean few years have passed in the manga, why is Tsuda still in second year, and why aren't Aria and Shino graduating from high school aren't they third years ?
anime and manga are sometimes like that, they want to add certain features for example onsen or hot spring but people don't exactly go to hot springs in summer, same as how they don't go to the beach in winter.

This might not be right but hope this helps