The Model of Conceptual Learning and Development (CLD) is an analytical, descriptive model. It defines four levels of concept attainment and the possible uses and extensions of attained concepts, specifies the cognitive operations involved in learning concepts at each of the four levels, and postulates internal and external conditions of learning related to the specified levels. The CLD model provides a basis for assessing children's level of conceptual development. The assessment of the level of conceptual development requires assessment tools and procedures appropriate for children ages 4-18. This working paper presents a set of exercises designed to assess children's level of attainment as well as use of the concept equilateral triangle. (Author/BJG)