The three Whole Foods Markets in Cambridge have vowed to donate 5 percent of their net proceeds Wednesday to the Friends of Cambridge Rindge & Latin School, a group that supports students and faculty at the high school through such things as faulty grants, student travel fellowships that allow students from low-income families to participate in school-sponsored trips and scholarships.

The grocery stores are at 200 Alewife Brook Parkway, 115 Prospect St. and 340 River St.

Update on Oct. 20, 2012: Money raised Sept. 12 at the grocery stores totaled $15,287, Whole Foods said, which was to be presented Oct. 18 at the high school.