The irrefutable relevance of science to humanity and national development through its applications in solving 21st-century global problems compelled the researchers to investigate science teachers’ awareness and utilization of innovative pedagogical approaches (IPA) for effective teaching of science in a 21st-century science classroom in Anambra State, Nigeria. The study which adopted a descriptive survey research design, was guided by four research questions and two null hypotheses. A total of 316 secondary school science teachers (131 biology, 98 chemistry, and 87 physics) were sampled using proportionate stratified simple random sampling technique. Data were collected using a 62-item structured questionnaire, developed by the researchers from teaching experiences and reviewed literature, with a reliability coefficient of 0.71 established using Cronbach Alpha. The data were collected through direct (face-to-face) administration of the questionnaire and analyzed using frequency counts, percentages, mean, and standard deviation to answer the research questions. Additionally, one-way Analysis of Variance (ANOVA) was used to test the null hypotheses at a 0.05 alpha level. The findings of the study revealed that science teachers utilize only 7 out of the 14 IPA they are aware of. This limited utilization is due to various challenges, including a lack of funds, insufficient time allocated to teaching science subjects, and resistance to change among teachers. In light of the results, it was established that science teachers only employ a few of the IPA they are familiar with. In line with the respondents' suggestions to address this issue, the study recommended that the government, in collaboration with other educational stakeholders, should provide funds, organize and sponsor educators to seminars, conferences and workshops to acquaint them with IPA and effective ways to incorporate them into teaching practices.