The Appropriateness of the Instrument in Assessing Children’s Early Mathematical Abilities

Lack of children's preliminary mathematics assessment skills causes the learning process in the classroom to be less optimal. This study aims to determine how the appropriateness of the instrument for assessing children's early mathematical abilities is seen from its validity and reliability. This type of research is development research (Research and Development) which is carried out using the RDR (Research, Development, Research) model. The subject of this study was an instrument for assessing the students' initial mathematical abilities which consisted of a grid and a questionnaire with a total of 14 items. The instrument for assessing students' initial mathematical abilities has been tested by two experts to measure the validity and reliability of the instrument. The results of the data analysis showed that: (1) 12 valid statements were made by calculating the validity of the student's initial mathematics ability assessment instrument of 0.75 with high validity criteria, and (2) the reliability of the student's initial mathematical ability assessment instrument was 0.80 with the criteria very high reliability. With the existence of an instrument for assessing children's early mathematical abilities, it can be used as a guide or reference for teachers in designing the learning process in the classroom, especially in mathematics learning.