This paper has dual aims. One is to analyze the results of interviewing four English teachers about focus on form approaches and corrective feedback techniques as well as English grammar teaching in elementary schools, focused on the necessity, the timing and the methods of grammar instruction. The other is to discuss strategies for integrating grammar instruction with communicative language use to propose effective grammar teaching approaches which can be implemented in the elementary school English classroom. The results of this study are as follows: Grammar should be taught to 5th and 6th grade students deductively, if necessary, as well as inductively since they will have to develop productive skills and written language skills to communicate more accurately with each other. Focus on form approaches are needed for students to pay attention to specific forms or correct their errors by themselves during communicative tasks under the teacher’s preferred corrective feedback techniques such as recasts, elicitation, repetition, etc. Two types of approaches are discussed to integrate grammar instruction with communicative language use. One is to design focused communicative tasks that focus students' attention on the predetermined specific forms during the tasks. The other is to provide reactive feedback explicitly or implicitly when grammatical errors occur while students’ primary attention is on meaning during the tasks. It is suggested that grammar can be taught to students at the intermediate level or above based on the former approach in which they can pay attention to specific forms, whereas it can be taught to most other students based on the latter in which they can receive the teacher’s feedback to correct errors, during communicative tasks.