Technology-based teaching and learning has been one way to improve students' achievement. However, some teachers are still unaware of how technology can be used to enhance teaching and learning, and they are also hesitant to use technology. This paper investigates how secondary school teachers understand and integrate technology to teach mathematics in the Musanze district of Rwanda. The paper takes a further look at the demographic factors associated teachers' use of technology. Using questionnaires composed of closed, open, and rating scale questions, 118 mathematics teachers were requested to express their understanding of using technology, how many times they use it, and their beliefs towards it. The collected data were analyzed using SPSS 23. Results revealed that teachers sometimes use "a computer, Internet Explorer, Microsoft Word, a spreadsheet, or a text message," but never use tools such as digital cameras, interactive whiteboards, dynamic software packages, or student response systems. The findings also revealed a significant relationship between demographic factors such as gender, level of education, and use of technology in mathematics teaching. This study suggests that teachers be trained in the use of technology in the classroom. They should be aware that there is no single method of teaching mathematics but a variety of approaches. It further recommends that teachers should be cognizant of various forms of technology and know how to use them in the classroom.