This study aimed to investigate the effectiveness of the WebQuests strategy on probabilistic thinking and the attitude towards probability among tenth-grade female students. The study used a quasi-experimental approach, with a sample of 63 tenth-grade female students from the South Al Batinah Governorate in Oman. The sample was divided into two groups: an experimental group consisting of 31 students and a control group of 32 students. The experimental group studied the prescribed unit using the WebQuests strategy, while the control group studied the same unit in the traditional way. To achieve the study objectives, the researcher developed the teaching materials according to the WebQuests strategy. The study tools included a probabilistic thinking test with 16 items and an attitude scale towards probability with 26 items. Validity and reliability of these tools were verified. The results showed statistically significant differences at the level (α = 0.05) in favor of the experimental group in the probabilistic thinking test overall, and in the informal quantitative and numerical levels. Furthermore, there were statistically significant differences at the level (α = 0.05) between the experimental and control groups' mean scores in the attitude towards probability scale overall, and in each of its domains, in favor of the experimental group. In light of these results, the study recommended several actions, most notably: utilizing the teacher's guide and the WebQuests website prepared in this study, familiarizing teachers with the levels of probabilistic thinking and methods to enhance them, employing the WebQuests strategy across all branches of mathematics and at various educational levels, and focusing educators' and teachers' attention on improving students' attitudes towards probabilities specifically and mathematics in general.