Philosophiae Doctor - PhD / The use of technology in mathematics education has many potentially positive outcomes. There is, however, little evidence to show where the use of technology has made a significant impact on mathematics education in South Africa. This study aims to address the issue of how computer tablets are currently used in the mathematics classroom. The researcher drew a comparison between learners who were taught with computer tablets and learners who were taught in the traditional way by evaluating the learners' progress after being taught on the topic of 3D images. This assessment was done in the form of a pre-test and a post-test that were administered to both classes on a topic of 3D images that was taught during this allocated time. The research is located in the third-generation activity theory. It is based on the socio-cultural theory of Lev Vygotsky, but it is blended with modern western theories as described by Engeström. The researcher made use of a mixed methods approach starting with a qualitative survey, followed by a pre-test, observations and concluding with a post-test. The pre-test and post-test determined whether cognitive knowledge was gained. The participants in the study were a group of 15-year-old learners at a private school where the one class was taught using computer tablets in the mathematics classroom, and the other class was taught the same content without computer tablets. A qualitative survey was sent to 27 schools within a particular school group where teachers indicated the popular Apps that were used in the mathematics classroom in this school group. Teachers also gave reasons why these were the Apps of choice and elaborated on how they were using these Apps. The quantitative part of this research was guided by the results of the survey and the 5 most popular Applications (Apps) were used in the teaching experiment. The quantitative part focused on two classrooms within the same school where the one class were taught with computer tablets and the other class were taught without the use of computer tablets. The t-test for this research showed that the group of learners who were taught with computer tablets achieved significantly better results than the class of learners who were taught using hard copy textbooks with traditional methods of teaching. This study showed that having computer tablets in schools can be effective in the mathematics classroom. The recommendations emanating from this study indicates that school who are planning to use computer tablets in the mathematics classroom should first plan their wi-fi capabilities with enough access points and internet access. These schools also need to decide on a type of computer tablet and what operating system to use. This decision has implications to the accessibility of quality Apps, battery life and storage space of the computer tablet. Schools are recommended to have a plan for training teachers in the use of this computer tablets especially regarding the pedagogical practice when interacting with learners. A last recommendation is to nurture a culture of computer tablet use amongst the learners to discipline themselves to charge and maintain their computer tablets and apply it to educational use. This study includes a pedagogical framework in respect of the effective use of computer tablets in the mathematics classroom.