Not sure about the trend in general, but this particular image (Anime girl holding a programming book) made me think it was a reference to these manga guides on

Not sure about the trend in general, but this particular image (Anime girl holding a programming book) made me think it was a reference to these manga guides on various math/science/engineering topics: https://en.wikipedia.org/wiki/The_Manga_Guides https://en.wikipedia.org/wiki/The_Manga_Guides