Speaking skills are crucial in the journey of English language acquisition, and students must acquire and master them to improve their proficiency in English. The literature indicates that ChatGPT has shown significant benefits in education, particularly in language learning, by providing interactive and personalized learning experiences. Several studies have highlighted its potential in enhancing speaking skills, as it allows students to practice and engage in real-time conversations, improving fluency and vocabulary acquisition. Therefore, this study aimed to investigate the efficacy of integrating an AI tool, ChatGPT, into English learning for grade 10 in Oman. This study aimed to answer the following research questions: Are there any statistically significant differences in the English-speaking skills of grade 10 students before and after using ChatGPT? And are there any statistically significant differences in the experimental group's motivation for learning English-speaking skills before and after the treatment? The study sample consisted of (N=93) female students from grade 10 from two different schools. Those students were divided into (n=46) students in the control group and (n=47) in the experimental group. The study is a quasi-experimental study comprising quantitative data collected by conducting a speaking test and a motivation questionnaire as the research instruments. The intervention of the quasi-experiment lasted for two months and was carried on for the 10th graders in Safiya Um Almoameneen School (5-10) in Al-Dakhiliah Governorate. Pre- and post-speaking test results and the ARCS motivation questionnaire results showed that ChatGPT's efficacy in improving the English-speaking skills of 10th graders for English language learning was not demonstrated as statistically significant. This may be due to several experiment limitations and restrictions, such as the availability of devices and the Internet. However, the experimental group's students improved their fluency and vocabulary range more than the control group after using ChatGPT. Furthermore, there was a statistically significant difference between the motivation tests of the experimental group students’ motivation toward the English language before and after the experiment, revealing a statistically significant difference in the satisfaction dimension. Some recommendations for further research in this area have been made, especially for the Omani context. These recommendations would involve the Ministry of Education and educational institutions to help teachers and students maximize the use of AI tools, specifically ChatGPT.