This MA study combines a descriptive analysis of 32 videotaped English lessons taught by seven teachers in seven classrooms at different lower secondary schools (Year 9), with interviews with two of these teachers. The data were collected as part of the Linking Instruction and Student Experiences (LISE) project, led by Professor Kirsti Klette and with Associate Professor Lisbeth M. Brevik as coordinator. The data were analyzed to identify grammar instruction in the English classroom, to characterize the students’ oral grammar mistakes in the observed classrooms and the teacher’s correction of these. Studying natural instruction (i.e., not interventions) in English classrooms is valuable in identifying grammar instruction practices on the one hand, and students’ grammar proficiency on the other. Integrating these analyses with teacher interviews provides an opportunity to examine English grammar instruction from different perspectives. I found that the students in the observed lessons seldom made oral grammar mistakes and that the teachers’ corrections of these were rare. The students’ oral grammar mistakes constituted a total of 374 mistakes (27%) out of 1382 clear student utterances in English, with the majority relating to verbs and determiners. When the infrequent correction of these grammar mistakes did occur, they were implicit and focused on the development of the students’ communicative competence, rather than correctness. This is in line with the notion that the English teachers’ error correction occurs to help students avoid being misunderstood. Moreover, while explicit grammar teaching occurred in two of the classrooms only, in these instructions, the teachers taught grammar rules based on students’ needs drawing upon a deductive teaching model. However, the teachers taught grammar out of context, rather than linking grammar instruction to either student texts or their oral communication. The teacher interviews suggest that as the LK06/13 English subject curriculum is vague when it comes to defining what areas of grammar to teach and how to teach it, teachers are left to decide how to approach grammar. Therefore, grammar instruction is often neglected. Nevertheless, the students’ infrequent grammar mistakes indicate that developing their ability to communicate successfully instead of focusing on producing grammatically correct utterances may be more important with regard to avoiding misunderstandings. These findings suggest that an integration of grammar instruction in the English instruction may be warranted, instead of teaching grammar out of context; bearing the students’ strengths and needs in mind to develop their communicative competence.