TheMat.com has announced its U.S.  women's college rankings for March. Missouri Valley College remains the No. 1 team in the nation, followed by the Univ. of Minnesota-Morris.    Moving up into the No. 3 team spot is Pacific Univ. of Oregon, which has good showings at the NAIA Coaches Association North American Championships, as well as the Can-Am Championships.  Lock Haven moves into the No. 4 spot, followed by No. 5 Cumberland College.    Two new athletes have moved up to No. 1 rankings in their weight classes: Jessica Shirley, a freshman at Cumberland College at 55 kg /121 lbs. and Tela O'Donnell, a freshman at Pacific Univ. at 59 kg/130 lbs.    Six athletes have remained No. 1 in their respective weight classes: Clarissa Chun of Missouri Valley at 48 kg/105.5 lbs., Patricia Miranda of Stanford at 51 kg/112 lbs., Sara McMann of Lock Haven at 63 kg/138.5 lbs., Toccara Montgomery of Cumberland College at 67 kg/147.5 lbs., Samantha Branka of UM-Morris at 72 kg/158.5 lbs. and Jenna Pavlik of Lock Haven at 77 kg/169.5 lbs.    Miranda and Montgomery claimed gold medals at the 2002 Pan American Championships earlier this month.    The bulk of the college season has concluded for women wrestlers, but the major part of the Senior-level schedule for USA Wrestling is coming up. Many of these college athletes are among the top wrestlers in the nation on the Olympic level, as well.    Complete individual and team rankings are posted on TheMat.com, in the rankings section.    TheMat.com U.S. College Women's Wrestling rankings will be published monthly on the following dates: Oct. 20, Nov. 20, Dec. 20, Jan. 20, Feb. 20, March 20, April 20, May 20.    Teams who are considered for ranking include both college varsity programs and college-affiliated club programs.    Athletes who are considered for ranking are eligible full-time college students, and are members of their college women's varsity or club program, or a member of their college men's wrestling team.     TheMat.com has created a composite schedule for women's college wrestling, which includes events from the U.S. and Canadian programs. Results from these events will be posted on a regular basis throughout the season.    Media outlets may reproduce these rankings only if they identify them as TheMat.com U.S. Women's Wrestling College Rankings