Abstract: Active learning is any learning activity in which the students participate or engage in the process of learning as opposed to the passive learning of taking information. Generally, students tend to have negative behaviour and cognitive aspects toward physics subject because they lack interest in physics and the syllabus itself. This study was carried out to study the students’ behaviours and cognitive aspects toward lower secondary school students in physics subject at Rwamagana district, Rwanda. A total of 246 participants participated in the data collection. Participants were selected from 4 schools selected purposively. The triangulation method was used to gather information. A qualitative research design was used to analyse and interpret the data from respondents. The study established that behaviours and cognitive aspects of the students are developed through the love and the value they express while they are learning physics subject. Positive behaviour and cognitive aspects are developed and improved depending on types of the teaching methods used by a teacher, in case the students are not satisfied or interested, teaching may be altered to the one which is helping and encouraging them to engage in the activity actively.