In Pakistani schools, science is taught through the expository method. The practical work is confined to teacher demonstration. Students work towards pre-determined results, following given instructions. This inhibits their thinking and development of scientific skills, such as hypothesising, predicting and concluding. One reason for this is that teachers are not aware of the new approaches to science teaching. The purpose of the study was to explore the problems and possibilities of using an investigative approach at a lower secondary level in one of the Government schools of Karachi. The research was carried out in three stages: pre-intervention, intervention and postintervention. The sample of the study was two teachers and nine students. They were interviewed before and after the introduction of an investigative approach. Participant observations, interviews, reflective journal writing, and photographs were among the techniques used for data collection. Several frameworks for scientific investigation are described in the literature. Evans's(1994) framework of an investigative approach was simplified and adapted to make it applicable in the Pakistani situation. Mentoring was used to provide support and guidance to the teachers in adopting an investigative approach. It was found that while using an investigative approach, students found themselves in the position of scientists which developed their interest and enthusiasm. Practicing problem solving skills helped them to understand the content in a meaningful way and the development of social skills changed the atmosphere of the classroom from a competitive to a cooperative one. The teachers also realized that an investigative approach was of great benefit to the students and proposed that it should be included in the science curriculum. The teachers also benefited from the study. Their questioning skills developed and they learnt to ask more probing questions. Working in pairs promoted collegiality and collaboration. They also found mentoring helpful for their professional development. Problems in introducing an innovation have also been investigated, these including lack of equipment, examination pressure, and short duration of periods.