Some common themes are unrequited love. It's quite frequent in manga high school love stories where one character has deep feelings for another who may not feel the same way initially. Then there's the theme of growth. Through the experiences of love, the characters grow both emotionally and in terms of maturity. And finally, the theme of family influence. Family backgrounds or expectations can either support or hinder the love relationships of the high school characters.
One common theme is the discovery of first love. In a high school setting in manga, characters often experience the butterflies and confusion that come with falling in love for the very first time. Another theme could be friendship intertwined with love. Friends may support or compete for the same love interest. Also, the theme of self - discovery through love is prevalent. As characters interact with their love interests, they learn more about themselves, their desires and what they truly want in a relationship.