The objective of this research was to develop teachers’ potential and educational personnel in term of authentic assessment under the Buriram Primary Educational Service Area Office 2 by using 2 cycles of action research. Each cycle included planning, action, observation and reflection. The research group consisted of 10 people, the target group was 36 people, and the group of additional information providers was 25 people. The research instruments were test, observation form, interview form, and record form (Triangulation) and presented the results of descriptive studies. The results showed that in the development of teachers and educational personnel in the first cycle used brainstorming strategies by a way of sharing opinions on the process of finding ideas and ways to solve the similar problem together, strategies for training workshops by using a lecture method to provide knowledge based on the content framework, practical training, consulting advice, questioning and participatory supervision strategies by observing teaching methods. This enabled personnel to have more knowledge and understanding of principles, procedures, and methods of measurement and evaluation based on authentic assessment. They were able to create authentic measurement and evaluation instruments and had the ability to measure and evaluate results based on authentic assessment by using a variety of measurement and evaluation methods. Most of the students cooperated in the activities but there were still some steps that the target group was unable to complete, that was the students had few activities and some target groups gave students less opportunity for self-report and self-assessment. Therefore, the development was carried out in the second cycle by using participatory supervision strategies by observing teaching methods. This enabled all personnel to have knowledge and understanding of the measurement and evaluation process, determined methods for measuring and evaluating according to authentic assessment, selected the correct evaluation methods according to the content. Measurement and evaluation with emphasizing on practicality and being able to measure and evaluate according to authentic assessment for teaching and learning. Most of the students participated in more activities and the measurement and evaluation based on authentic assessment.

The objectives of this research were to construct and verify a mathematics diagnostic assessment on addition and subtraction basis for grade 4 students in Buriram Primary Educational Service Area Office 3. The research samples consisted of 440 Prathomsuksa 4 students selected by adapting the multi-stage random sampling method. The research instruments employed in this research comprised of two types of examinations constructed according to strand 1: number and algebra in Mathematics 1.1. The tests were to examine test and diagnostic test. The examining test was a subjective test, consisted of 80 items which divided into addition part for 40 items and subtraction part for 40 items. The diagnostic test was a multiple-choice with 4 choices tests, consisted of 48 items which divided into addition part for 24 items and subtraction part for 24 items. The diagnostic test. The results showed that the content validity, determined by the expert, had the IOC score at 0.60-1.00. The addition part in the 1st test had a difficulty score of 0.21-0.79, the discrimination score at 0.23-0.89, and the reliability score at 0.89. The subtraction part in the 2nd test had the difficulty score at 0.31-0.72, the discrimination score at 0.32-0.72 and the reliability scores at 0.32-0.81.