AU - Alomiear, Maha Ibrahim AU - Alreshidi, Ahmed Mubarak AB - The study aims to investigate some characteristics of fourth-grade mathematics teachers in Saudi Arabia and the United States of America, which may affect students' mathematical achievement. Thus, the research utilized fourth-grade students' data, as the average score of students was (398) compared to (535) in the Unites States. Post fact design was used with a sample of (4174) students and (170) teachers in Saudi Arabia, and (8353) students and (451) teachers in the United States. Result indicated that teacher's gender, age, educational level, and qualification are significant variables that impact mathematical achievement in Saudi Arabia. Results also showed that teachers' years of experience, hours of professional development spent by the teacher during the past two years, and teacher gender are significant variable which impact students' mathematical achievement in America. As for the teachers' gender, findings showed significant differences were in favor of students taught by female teachers in both countries. (Published abstract) http://search.shamaa.org/abstract_en.gif OP - pp. 91-128 T1 - Do characteristics of teachers affect students' mathematical achievement? a comparative study between Saudi Arabia and the United States of America according to (TIMSS 2019) [Article] UL - http://search.shamaa.org/PDF/Articles/FC/ERIjres/IjresVol5No1Y2022/ijres_2022-v5-n1_091-128_eng.pdf Full text (PDF) 1 http://search.shamaa.org/fulltext.gif