The purpose of the study was to investigate effects of demonstration and discussion teaching methods on attitude and retention of urban and rural students in senior school biology in Yenagoa and Ogbia Local Government Areas. Quasi-experimental research design was employed. The population of the study was 6,988 Senior School Two Biology students in Bayelsa State. The sample consisted of 323 Senior School Two students from 23 Senior Secondary Schools in the above Local Government Areas of Bayelsa State. Two research questions and two hypotheses guided the study. Three validated and reliable instructional guides namely Instructional Guide on Demonstration Teaching Method (IGDTM), Discussion Teaching Method Guide (DTMG) and Guide on Lecture Teaching Method (GLTM) were used in training teachers to use the methods of teaching. Standardized Biology Achievement Test (SBAT) was used as a reliable instrument for data collection. Data were analyzed using percentage, mean, standard deviation and z-test statistics. The findings of the study showed no significant difference in retention mean scores of SS2 students in urban and rural schools when taught with demonstration and discussion methods. Also, there was slight increase in attitude of students in pretest and posttest in all the groups but when subjected to z-test analysis, it showed statistically not significant in all the groups. These implied that adequate consideration to teaching methods in biology is crucial to enhancing attitude and retention of students during lessons as school type does not affect students’ attitude nor improve academic achievement.