Do we sometimes stereotype a book as being for girls or boys exclusively? Are girls and boys seeking different things in books. Research from a quarter of a century ago did suggest there was a gap between what boys and girls wanted in books. This article shares some studies of gender's role in reading: https://www.ucy.ac.cy/unesco/documents/unesco/Articles_2010-2010_conference/GRIVA_ALEVR_SEMOG_paper.pdf"Furthermore, a lot of researchers have investigated and indicated differences between male and female students in reading preferences, reading performance and strategy use (e.g., Biigel & Buunk, 1996; Chavez, 2001). In addition, a number of studies have revealed gender differences in the amount of time allocated/devoted to reading. It has also been found that a higher percentage of girls indulge in leisure reading than boys (Abilock, 2002; Swalander & Taube, 2007). The females show a more positive attitude to reading (see Swalander & Taube, 2007) and a preference for reading a variety of genres compared to males (Clark, Osborne & Akerman, 2008)."
More recent research seems to point to more individual differences rather than issues of gender: http://fisherpub.sjfc.edu/cgi/viewcontent.cgi?article=1207&context=education_ETD_masters.
I think perhaps the most important thing to do is to survey our OWN students about their habits and preferences. And we need to be certain we are sharing a wide variety of books in terms of genres, forms, formats, etc.