The intent of this explanatory sequential mixed-method study is to examine Islamic teachers thoughts on improving critical thinking skills in elementary schools in the Southwestern province of Saudi Arabia. This study involves the collection of quantitative data and an explanation of the quantitative results with qualitative data. In the first phase, a survey is administered to Islamic teachers in Saudi elementary schools to assess their opinions on improving students' critical thinking skills and to investigate the factors that influence or hinder their implementation of critical thinking instruction. In the second phase, qualitative data is collected using semi-structured interviews with a number of Islamic teachers in order to explore more fully their perceptions toward improving students' critical thinking skills in Saudi elementary schools. The reason for collecting both quantitative and qualitative data is to obtain a better understanding of the gathered information than would be possible using only one of these methods. In regard to the barriers for improving the critical thinking ability in elementary education students, the study participants reported seven major obstacles, which are student ability, teaching methods, classroom structure, Saudi society and the school community, pre-service teachers preparation programs and in-service teacher professional developmental programs, and the Islamic studies curriculum. The highest ranked obstacle was student ability, with an overall mean of 4.31. Teaching methods, with a total mean of 4.29, was the second most cited barrier. The third was classroom structure, with a total mean of 3.72. The study participants ranked society and school community as the fourth obstacle, with a total mean of 3.70, and pre-service teachers preparation programs and in-service teacher professional developmental programs with a total mean of 2.69. The Islamic studies curriculum was ranked sixth in obstacles to improving critical thinking for elementary education students, with a total mean of 2.57. These findings suggests there is a need to examine female Islamic teachers' perceptions toward critical thinking in the Southwestern region of Saudi Arabia in order to identify the similarities and differences between the perceptions of male and female teachers. It is vital to investigate perceptions of teacher of other disciplines, such as language art, social science, English, and math, in an effort to provide policy makers in the Ministry of Education with a holistic picture of the Saudi educational system. Qualitative studies, interviews with students, and classroom observation can be carried out to investigate students' perceptions as to how critical thinking is taught in the classroom and whether teaching style is a primary obstacle to it being taught. There is an urgent need to examine in depth the influence society and the school community has on teaching students' thinking in general and critical thinking in particular. Finally, more research is needed on the pre-service education programs and in-service professional training programs in terms of building teaching programs on critical thinking skills.