Instrument Test Development Of Mathematics Skill On Elementary School

-The aims of this research are producing the test instrument of mathematics skill on elementary school which is valid and reliable. The instrument test development in this research use the development model of Wilson, Oriondo and Antonio which is modified. The number of testing sample in this research is 160 of students in each class. This research result: 1) the validity index of aiken v is 0.979 in grade IV and 0.988 in grade V. The coefficient of instrument skill in class IV and V are 0.883 and 0.954. The case indicates that the overall item is accepted and reliable to be used for measuring the development of mathematics skill of elementary school students.


INTRODUCTION
Elementary school is an educational institution which has a function to impart the basic ability and skill for the necessity of the lesson continuity on higher level education, and to give the skill provision for students to make self-development which is suitable for their ability and interest, as well as their environment condition. The ability in counting and measuring as well as reading and writing skill in elementary school are the basic for other skills development which is higher.
For instance, National Council of Teachers of Mathematics (NCTM, 2000: 16) propose that the development of mathematics skill of students in class K-2 usually can explore the similarity and the difference on two dimensions shape, in class 3 to 5 they are able to identify the characteristics of various rectangular, in class 6 to 8 they are able to check and Research Article Vol.12 No.6 (2021), [2447][2448][2449][2450][2451][2452][2453][2454][2455] make a generalization about the characters of certain rectangular, and in class 9 to 12 they are able to develop the logic argument to confirm the notion about certain polygon. The case gives the description that the mathematics skill develops from early age to mature or the mathematics skill develops from kindergarten level to high school level.
The result of Trends in Mathematics and Science Study (TIMSS) (2012) which is followed by Indonesian students of class VIII in 2011 show that for mathematics field, Indonesia is in 38th place with the number of scores is 386 of 42 countries. This score decreases eleven points from the rating in 2007. Program for International Student Assessment (PISA), hold the survey about students' skill and educational system, where the students' skills assessed in this survey are mathematics, reading and science skill which reflect the educational system in each country. The result shows that students' mathematics skill in Indonesia was ranked 64 of 65 countries or second order from the bottom with the number of scores is 375.
The survey result indicates that Indonesian students' mathematics skill is still low both in content dimension and cognitive dimension. The content dimension assessment on the domain: numbers, algebra, geometry, data and probability. Meanwhile, on the cognitive dimension assessment in domain: 1) knowledge, including the facts, concept and procedure which should be known by the students, 2) applying, which focus on students' skill in applying the knowledge and concept understanding to solve the problem or answering the question; 3) reasoning which focus on problem solving non-routine, complex context and taking many problem-solving steps. On the survey conducted, Indonesian team is only followed by students of class VIII or Research Article Vol.12 No.6 (2021), [2447][2448][2449][2450][2451][2452][2453][2454][2455] junior high school students, while students of class IV or elementary school students are not included in the survey. This case is necessity to be conducted a further research to assess the students' mathematics skill in class IV or in elementary school level. The assessment is crucial to be conducted in order to give the information about the development achievement of students' mathematics skill or how far students have mastered the competency that they want to reach as a result of the learning.

Determining the Test Goal
On the initial test stage, first that should be done is determining the test goal. The instrument includes summative test due to it is given the chance at the last stage of learning or final semester. So, the aim of the test is to know the students' mathematics skill in grade III, IV and V on elementary school.

Determining the Competency Tested
After the objective of the test are clear, then selected the competency which will be tested. This competency is suitable for core competency (CC) and basic competency (BC) for mathematics grades III, IV, and V elementary schools. Based on core competency and basic competency determined indicators that correspond

Arranging the Test Grid
To be able to make a good question item, it is required the test grids. A grid is a matrix containing the specification of the test items made. This grid is a reference for writing the question, so by the test grid, whoever writing the question will produce the question and the difficulty level which is relatively the same.

Arranging Scoring Guidance
The test can be used, if it is completed with the scoring guidance. Scoring guidance is designed to maintain the objectivity of assessment and score certainty obtained by the participant of the test.

Content Validity of the Test
After the items are compiled in the math skill test in grade III, IV, and V of Elementary School and the scoring guideline is conducted the limited trial. This limited trial was conducted with the aim to find out the readability of the test details. Limited trial results are used as the basis for revision and refinement of the items. Besides limited trial, in order to obtain good instruments, the lattice of instruments, items, and scoring guidelines that have been compiled are subsequently reviewed, and validated. The validation process, in order to meet the requirements in terms of concept, construction and language is used with expert's judgement.

RESULT AND DISCUSSION
One of the educational problems related to the quality of education is the low mastery of students toward the competence, as a result of students' inadequate assessment. The assessment system is not optimal because: (1) the quality of tests made by teachers is still inadequate, (2) the monitoring of the testing network in the area has not been conducted properly, (3) the reporting of exam results has not been optimal, and (4) the utilization of exam results has not been done optimally.

Content Validity of the Instrument
Validity is classified into three types, such as: (1) validity of content, (2) validity of criteria (criterion-related) and (3) validity of constructs (Nunnally, 1978, Allen & Yen, 1979, Fernandes, 1984, Woolfolk & McCane, 1984, Kerlinger, 1986, and Lawrence, 1994. This validity can be found out through the analysis of the contents of the test and empirical analysis of the test score of grain response data (Lissitz & Samuelsen, 2007). The validity of the contents of an instrument is defined as to what extent the items in the instrument represent the components in the entire content of the object to be measured and to what extent they reflect the characteristics of behaviour to be measured (Nunnally, 1978;Fernandes, 1984).
The validity of the content is determined by using expert agreement. Expert agreement of the field of study or often referred to as a measured domain determines the level of validity of content related (Heri Retnowati). This case is caused by the measurement instruments, such as tests or questionnaires are proven valid only if the expert believes that the instrument is able to measure the mastery of the capabilities defined in the measured domain. Analysing the validity of the content uses the aiken formula.
The instrument can be stated valid if the expert believes that the instrument measure the things which will be measured. Expert judgement gives the scoring used that will be used to prove the content validity toward the number of instruments in this research. The instrument that will be validated are as follow:

Reliability of Instrument
The reliability of a test is generally expressed numerically in a coefficient of -1.00 ≤ ≤ +1.00 (Retnawati, 2016 Table 3 is the estimation result of the reliability on the research instrument developed.
This research estimates the reliability on the instrument in grade IV and V where on each instrument consists of 40 items of questions.  Based on the results of the analysis showed that the coefficient of reliability instrument of grade 4 is 0.883, package instrument of grade 5 is 0.954, it is concluded that all instruments developed can be stated reliable. It shows that all items are accepted and reliable to be used to measure the development of math skill of elementary school students.