Mastering concepts and ability to relate among concepts to solve problems can build students’ schema. A schema of a mathematic concept refers to a set of action, process and object which are related to a number of principles to build an individual’s ways of thinking to solve a given problem. The schema construction in the current study is based on the analytical framework of the APOS theory (Action, Process, Object, and Schema). The current study aims to describe and analyze “Schema Construction Profiles among Elementary School Students in Solving Problems Related to Operations of Addition to Fractionsâ€. Analyses were done quantitatively on the basis of the analytical framework of the APOS theory. Results show that students of high and middle ability indicate that they did not encounter serious difficulties in their schema construction (able to do according to the APOS theory). Those of low ability, in contrast, encountered relative difficulties.