This study determined the effect of the combination of conventional lecture and Facebook discussion on the Achievement Pre-service Integrated Science Teachers in an Organic Chemistry course in the College of Education. Two research questions were raised, and one hypothesis was tested. The study adopted a pretest-posttest quasi-experimental research design was adopted. A total of 135 Pre-Service Integrated Science Teachers (PSIST) selected using multistage sampling technique were the participants in the study. The main instrument for data collection is Carbon Chemistry Achievement Test, and three other instruments were stimulus instruments. The data collected were analysed using frequency counts, simple percentages, estimated marginal means and analysis of covariance. The result indicates that the PSIST exposed to conventional lecture and Facebook discussion performed better in Organic Chemistry with a significantly higher mean score than their counterparts exposed to traditional lecture alone. It was concluded that integrating Facebook, the leading Web 2.0 communication technologies with teacher education, will ensure better performance of teachers.