How to keep my apartment cool?

I live in Texas, so the weather is around 100 degrees farenheit every day. In my house, it is 80-81 degrees. All of my windows have energy-efficient window curtains around them, I don't use the dishwasher during the day and I don't cook during the day because it gets too hot. I am pregnant and I have a 14 month old son. I think it is too hot for the both of us. What else can I do to make the temperature go down? I do not want to open windows because all of my windows face east and west, so it would get hotter because the sun rises and sets in those windows (they are also bay windows, but I have them fully covered with the window curtains). I also have a small fan that I use during the day.