Effective instruction is vital for quality education in Kenya, with learners' success mainly dependent on structured methods like the five-stage lesson plan (5-SLP). Nonetheless, the effectiveness of instruction may differ depending on the demographic and professional attributes of the teachers. Although the value of planning for content delivery is well acknowledged, there is limited information on how teachers' characteristics (age, gender, experience and academic qualification) influence their planning and content delivery. Thus, this study examined the relationship between teachers' planning and content delivery through the 5SLP, focusing on their characteristics. A sample of 226 CRE teachers was analysed using an observation checklist and a semi-structured questionnaire. The impact of gender, age, experience and academic qualification on teachers' planning and content delivery was investigated in the study using multivariate analysis of variance (MANOVA) and tests of between-subjects effects. Results indicated that age significantly affects both planning and content delivery (p = 0.003, p = 0.002, p = 0.000), while gender, experience and educational qualifications did not show a substantial impact. Nevertheless, significant combined effects were observed between age and gender (p = 0.010), gender and experience (p = 0.045), age and experience (p = 0.004) and age and academic qualification (p = 0.016). Furthermore, tests of between-subjects effects indicated significant interactions among age, academic qualifications and experience (p = 0.039, p = 0.016, p = 0.004) affecting content delivery. The study findings recommended a policy on the need for customised training programmes that consider these complex interactions to enhance instructional effectiveness. Generally, the study contributes to understanding how demographics influence educational practices, offering valuable insights for improving teacher preparation and professional development.