Within the "Australian Curriculum: Mathematics" the Understanding proficiency strand states, "Students build understanding when they connect related ideas, when they represent concepts in different ways, when they identify commonalities and differences between aspects of content, when they describe their thinking mathematically and when they interpret mathematical information" (ACARA, 2012). Concept maps can be used to organise and represent the connections in knowledge graphically which allows teachers to assess the connections that students make between concepts (Novak & Cañas, 2008). This article explores the use of concept maps with a Year 9 mathematics class to determine their understanding and the connections that they make between concepts within a measurement unit. The findings show the importance for teachers of Year 7 to help their students to see the connections between these concepts when they are first introduced.