Abstract: This study reports on an exploratory study in which questionnaires assessing the understanding of grade 4 Mathematics concepts learnt as prescribed by Continuous Assessment Policy Statement (CAPS) were administered to 219 grade 5 learners from 20 randomly selected primary schools in the Limpopo province of South Africa at the beginning of the year 2014. This study reports only on the understanding displayed in responses to five out of twelve questions that sought interpretation of geometric concepts in the questionnaires. This was a both quantitative and qualitative study in which structured and semi-structured interviews were conducted with six learners on the basis of their responses to gain more insight into how they constructed their geometric meanings. Results indicated that some learners did not understand the questions but would respond to questions based on a word or diagram that they associated with a particular concept. Nonetheless, 99% learners displayed understanding and familiarity with the concept of similarity. It can be recommended in this study that the interpretation in some questions be explained using African languages that were used in the learners’ previous grades. Also, the use models like photos, diagrams, graphs, symbols, icons and other visual representations can help promote the conceptual understanding of geometric concepts to learners in the intermediate phase. The study therefore concludes that for learners to interpret geometric concepts in the intermediate phase, their geometric vocabulary should be developed such that they are able to make connections between new ideas and their prior learning.