This study aimed to identify the effect of using the numbered heads strategy on academic achievement and creative thinking in mathematics for sixth grade students. The researcher used the quasi-experimental approach, and the study sample consisted of (60) students from the sixth grade students, at Imam Salem bin Rashid School for Basic Education (5-12), they were randomly divided into two groups: an experimental group consisting of (30) students who studied a unit "(1a) Numbers and Problem Solving" using the numbered heads strategy, and a control group consisted of (30) students who studied the same unit in the usual way, and it was confirmed that the two groups were equal in achievement and creative thinking previously. To achieve the purposes of the study, the researcher prepared the educational material for unit "(1a) Numbers and Problem Solving" for the sixth grade, and validation was done by expert judgment. Two study tools were prepared: one is an academic achievement test, and the other is a creative thinking test. Both tools were checked for their validity by reviewing them by a group of experts. Moreover, they were checked for their reliability by using internal consistency method (Cronbach's alpha method) which was (0.851), and (0.844) respectively. To answer the questions of the study, the researcher used t-test and Pearson correlation coefficient. The results showed that there were statistically significant differences at the significance level (α = 0.05) between the mean scores of the sixth grade students of the experimental and control groups in the creative thinking test, and the post-school achievement test in favor of the average scores of the experimental group. The study recommended paying attention to using the numbered heads strategy in teaching mathematics, as it has an effective impact on academic achievement and the development of students' creative thinking skills, and its use in various educational fields.