This study had the purpose of testing two methods for teaching grammar in English as a Foreign Language (EFL) class: the deductive and inductive approaches in terms of effectiveness and rapport. This research was conducted in a public high school in Ecuador. Seventy students enrolled in the second year of senior high school participated. One in-service teacher taught the EFL classes during the process of intervention (10 weeks), and two EFL teachers observed all of these classes and recorded the information by filling in observation sheets. The students were administered grammar pre-tests and post-tests in order to assess their grammar knowledge. The results of the tests showed a significant difference in the scores in favor of the inductive approach. After the statistical analysis of the data obtained from the tests and observation sheets, we concluded that the inductive approach is more effective for teaching grammar in the EFL classroom in terms of instruction and rapport.