68 Fortes, E., et. al. (2014). Development of micro-scale mathematics kits Research article DEVELOPMENT OF MICRO-SCALE MATHEMATICS KITS Erminda C. Fortes Olive Buzon, Aurora Gonzales, Antonio Ferrer, Rosemarivic Diaz, Robert Diaz, Myla Esperanza, Blesilda Infante, Wilmer Marquez, Gladys Nivera, Reymond Quan, & Allan Reyes Abstract The use of manipulative devices in classrooms has been studied for years, and results have yielded a better understanding of mathematics concepts and principles. However, despite positive results regarding teaching mathematics with manipulative devices, many mathematics teachers still hesitate to use them in teaching, primarily because they do not know how to, and when to use them. This drove the researchers to design and construct thirty prototype manipulative devices and write accompanying lesson plans that would guide Kindergarten to Grade 10 teachers when using them in mathematics classes. Both these instructional support systems received “outstanding” evaluations for their content/face validity. Having established the content/face validity of the manipulative devices in each MATHEMATICS KIT, cum accompanying lesson plans, it seemed that: (1) the former devices may be used to develop different concepts in Kindergarten to Grade 10 Mathematics, and (2) the latter to guide mathematics teachers in using the manipulative devices in classrooms. Keywords: manipulative devices, micro-scale mathematics kits INTRODUCTION Learners often struggle to grasp the abstract mathematics concepts taught in elementary and high school. During this period,