The study Investigated the Quality of Basic science and Technology Teachers’ Lesson Preparation and teaching behaviours on classroom interaction in North central zone of Plateau State, Nigeria. A descriptive survey design was employed. The population comprised of all Primary four teachers teaching Basic Science and technology and their pupils in the North central zone of Plateau State. 20 Primary four teachers teaching Basic Science and technology and pupils drawn from five local government schools in the North central zone of Plateau State form the samples of the study, Observation of teacher lesson preparation and classroom teaching was used as instruments for data collection. Sound recorders were used to collect data on all verbal interactions between teachers and pupils. A Cool Edith programme was used to measure the unproductive wait time of teachers’ questions and the length of response of pupil. Bloom’s category system was used to analyze the type of questions asked by teachers and pupils. Research assistants were used to collect data. Seven research questions guided the study; the result shows that some primary four teachers teaching Basic Science and Technology do not prepare their lessons well before teaching and are deficient in managing pupils thinking in the classrooms. A behaviour modification training programme was recommended for training of Basic Science and Technology teachers to improve their lesson preparation and teaching of Basic Science and Technology to promote pupils’ thinking and achievements in primary schools in Nigeria.