Grass Week Marine Corps Sgt. Raymond E. Jackson, a drill instructor, leads his platoon during grass week at Marine Corps Recruit Depot, Parris Island, S.C., Dec. 4, 2017. The purpose of grass week is to teach recruits shooting positions and weapon safety rules. Marine Corps photo by Lance Cpl. Yamil Casarreal SHARE: Download: Full Size (0.97 MB) Tags: Marines, Northcom, Northern Command, training, Featured Photos, Marine Corps Credit: Lance Cpl. Yamil Casarreal VIRIN: 171204-M-JY586-075D.JPG Photo Gallery