Very nice, I like the colour-scheme.
You might want to change the following line:
.sideblocklinks {
background-image: url(
);
}
to
.sideblocklinks {
background-color: transparent;
)
to prevent the odd-looking repetition of the background image within the Main Menu, Courses and Activities blocks.
Assuming that you only want the embellishments along the sides of the boxes, the images texture2.jpg and texture3.jpg should probably be extended or else you get unwelcome repeats of the pattern in larger blocks. For texture3.jpg (the heading) I think extending it downwards another 50 pixels should be fine for headlines that wrap onto a second line. The lighter background (texture2.jpg) you probably need to extend it out to 600 or so pixels, maybe 800 to be safe to prevent repitition in places like the login screen.
hope that helps, and congrats on the nice theme.