I found some interesting statistics, at least for my school.
Distribution of Student Majors by Gender and Ethnicity
Engineering
Science
Applied Sciences & Arts
Social Work
University Total
Note that in engineering and science, the gender bias disappears in graduate students. Well, for the college totals at least; some of the majors are still biased.
The engineering majors (undergraduate) with the smallest biases are chemical and industrial systems. The most biased ones are mechanical and computer.
As for science, I was right about there being a large bias toward women in biology, but chemistry was close to even.
There are 3 times as many women in chemistry than chemical engineering. Oddly, computer science is 23% women, but computer engineering is only 14%.
Excluding biology, the College of Science is 29.6% women (39% with biology). The College of Engineering is 16.3% women. 70.1% women in the College of Applied Sciences and Arts. In total, San Jose State University is 50.6% women.
If you want to comb through other data, you can find an index of all the tables
here.