This study was conducted to compare the efficacy of Lecture-Based-Learning (LBL) and Cooperative-Learning (CL) in teaching 'classification of living things' to Senior High School (SHS) students in Tamale, Northern Region, Ghana. The study was conducted in two SHSs using two science classes offering Biology during the 2020-2021 academic year. A pretest-post-test nonequivalent quasi-experimental design with two experimental groups was used. A total of 75 students from two intact classes participated in the study. One of the classes (School A) comprising 39 students was taught using LBL while the other class (School B) comprising 36 students was taught using CL. The study used a teacher-made test to collect the data. The data was analyzed using reliability analysis and a t-test in SPSS. Results revealed that CL recorded a mean score of 30.33 and was more effective (p < 0.001) than LBL which recorded 23.26. In conclusion, CL methods should be encouraged to enhance students' performance and retention.