FOOTBALL  Friday, Aug. 15  Navasota at Giddings, TBA  Brazos Christian at Iola, TBA  Caldwell at Anderson–Shiro, 5:30 p.m.    VOLLEYBALL   Aug. 14–16,   Navasota Lady Rattler Tournament  Iola at New Waverly Tournament  Anderson–Shiro at Leon Tournament  Tuesday, Aug. 19  Somerville at Navasota 5/6 p.m.  Iola at Montgomery, 4:30 p.m.  Richards at Dime Box, 5 p.m.  BVCHEA at Anderson–Shiro, 4:30 p.m.    TENNIS  Monday, Aug. 18  Navasota at La Grange, 4:30 ...