This study investigated the effect of Blackboard-based instruction on pre-service teachers' achievement in the teaching methods course at The Faculty of Education for Girls, in Bisha, KSA. Forty seventh-level English Department students were randomly assigned into either the experimental group (N=20) or the control group (N=20). While studying their teaching methods course, the experimental group received instruction via Blackboard Collaborate, whereas the control group received traditional instruction. The two groups were pre-post tested using a teaching methods test prepared by the researcher. Two hypotheses were formulated and tested. Results obtained from Wilcoxon Signed Ranks Test and Mann-Whitney Test revealed that Blackboard-based instruction was effective in enhancing the achievement of the experimental group. In addition, compared to traditional instruction, Blackboard-based instruction was more effective in improving the participants' achievement as it provided them with multiple opportunities to explore alternative means to interact with teachers, peers, course material and activities.