KNOWLEDGE, ATTITUDE AND BEHAVIOR ON REPRODUCTIVE HEALTH OF 10TH GRADE STUDENTS IN TWO HIGH SCHOOLS IN NAM DINH PROVINCE 2003 The results of cross - sectional descriptive study using qualitative and quantitative method about knowledge, attitude and behavior on reproductive health of 10th grade students in two high schools in Nam Dinh province showed that: 1) There were 8% of female students and 11% of male students not to know the sign of puberty of their gender; 17% of students to know correctly about the time to be easy to get pregnant in menstrual cycle; 13% of students not to know any contraceptive method.