N.A. Al-Najar and F.S. Al-Afari 2020. The effectiveness of using a computerized package to development of geomorphological concepts and visual thinking skills of the 10th grade female students in Oman. Journal of Educational Sciences – Qatar University. 15, 15 (Jun. 2020), 39–67. DOI:https://doi.org/10.29117/jes.2020.0021.