This study reports on comparing the presentation of mathematical content, types of responses required of students, conformity with the curriculum outcomes, and potentially confusing expressions in the subjects of percentages, triangles, and quadrilaterals of fifth-grade mathematics textbooks used in Turkey and Singapore. Document analysis of the two mathematics textbooks indicated that both books remained committed to achieving the curriculum outcomes, that the content of the Singapore textbook was more simply organized, and that the Singapore textbook included more visual representations and multiple solution strategies. The analysis also showed that the questions requiring numerical responses were common in both textbooks, while the Singapore textbook included relatively more questions requiring both response and explanation. The findings also indicated that the Singapore textbook was comparably more error-free; however, the Turkey textbook involved several difficulties concerning syntactic errors, ambiguity, unrealistic task presentation, redundant operation, unclarity in mathematical purposes, and weak mathematical context. We discuss the usefulness and intelligibility of mathematics textbooks regarding established cultural and philosophical traditions and trust and respect for textbooks.