I recently read a book that documents studies that show the biological and neurological differences between boys and girls and men and women. It's called, "Why Gender Matters," by Leonard Sax, M.D., Ph.D. He is a major advocate of same-sex schooling and there were many things I found very interesting, especially since I'm teaching both girls and boys in my family.
Did you know that girls' eyes have more cells that are best adapted to detect color and texture, whereas boys' eyes have more cells that are best adapted to detect location, direction, and speed? So when little girls draw pictures, they draw nouns like flowers, trees, and people using lots of colors and little boys draw pictures with action using fewer colors like black, blue, gray, and silver.
That's just one of the biological differences. Men and women have different brain structures. Boys and girls develop different parts of their brains at different times, so if girls are developmentally ready for reading, for example, boys may not yet be ready. I found it fascinating.
I also read Dr. Sax's subsequent book called "Boys Adrift," detailing the reasons he's found that boys and men in our generation are generally not succeeding as well as girls. These factors include our current gender-neutral educational system, video games, and endocrine disruptors.
I encourage anyone who has children, especially those who have boys, to read these books. They definitely gave me food for thought. If you want to learn more, I'll put the links to these two books below.