The study aimed to figure out the effectiveness of using interactive learning website for teaching social studies to develop achievement and critical thinking of 10th grade students in Sultanate of Oman. To achieve the study aims ,a quasi-experimental approach was used. The sample consisted of (52) students from boys & girls of Al-Bareek Primary School - 10th Grade and was divided to two categories: The experimental group consisted of (26) students who were taught by using the interactive learning site and the control group which was taught by the used method. The equality of the two groups was investigated by using the application of the pre – test of school studies development and critical thinking . Data were collected by achievement test of (23) questions and critical thinking test of (20) questions were approved by referees. The reliability of the tests was verified and the Alpha Cronbach Coefficient was (0.711), and critical thinking was (0.712). The study results showed that there was statistically significant difference at the level (0.05=a) between the two groups in favour of the experimental group, where the website contributed in the enhancement of studies and development of critical thinking among students.