If you want to learn more about the aircrafts and its various elements which makes it to fly, then there is no better site
than this. This site gives you complete details about the ailerons, flaps, rudder and interestingly you can download the applet to see the animation on how the various elements move up & down to make the aircraft move in air. I have sent this link to many friends of mine & they have appreciated the contents of this site. In addition to this you can browse for NASA history, shuttle schedules and many interesting things...really interesting.