A study published in Developmental Psychology found that boys’ higher math scores result more from better spatial skills than girls’ low self-confidence. Researchers tested 94 high school students on their math self-confidence and their spatial skills, the ability to mentally visualize and rotate 3-dimensional objects. They discovered that 64% of the difference in math scores stems from boys’ better spatial ability, while 36% results from girls’ lower self confidence. M. Beth Casey, a developmental psychology professor at Boston College and the report’s leading author, believes boys obtain better spatial skills because their elders encourage them to play with blocks and toys such as model airplanes at early ages and to participate in sports. Casey says girls’ math skills would benefit from the same encouragement.