FYI, in the year 2005, CatholicSupply.com is offerring: two kick pleats front and back, knife pleated full round, kick pleat culotte full round, and culoote with front and back flaps. They do, however, mention kilts in the heading on that page.
http://www.catholicsupply.com/uniforms/uskirt.html

A search of that website turned up one school that has kilts as part of the uniform, Bishop DuBourg High School in St Louis, Mo. I looked up their dress code and the kilt is intended for the girls; there is no mention of kilts in the boys dress code.

I also found several schools on-line that mention kilts as part of the girls dress code but the only image I could find was a hand-drawn picture at another uniform supply place http://www.flynnohara.com/mGirlsStyles.asp?nav=0105