Mental Mathematics

This research was motivated by many elementary school students’ lack of proficiency in doing basic mathematics calculations such as addition, subtraction, multiplication, and division. In this research, we focused on examining how to help the students master subtraction.
Preliminary studies had been conducted by the researchers in Perumahan Bumi Public Elementary School, Kelapa Dua, Tangerang, Indonesia. It had showed that students of grade V faced difficulties in doing subtraction. This study had been done by giving a fifteen-minute written subtraction test to 13 grade V students. The mastery level achieved had been 67.2%. In addition, a mental subtraction test was given to 7 grade V students. This was to investigate students’mental subtraction ability. Each student was given 8 seconds to answer each question mentally. The mastery level achieved was only 39.43%.
This research was conducted using qualitative research method. The sample of this research was 9 students of grade V Perumahan Bumi Public Elementary School, Tangerang, Indonesia. Subtraction was taught to these 9 grade V students using an innovative learning method called Matematika GASING, which had originally been developed by Prof. Yohanes Surya at the Surya Institute, Indonesia. Matematika is the Indonesian word for mathematics and GASING stands for Gampang (easy), Asyik (fun), and Menyenangkan (enjoyable).
This research concluded that Matematika GASING helped students in learning subtraction. The mastery level achieved in the written test taken after the learning was 92% (an improvement from the test taken at preliminary study). Students had a positive opinion towards learning subtraction with Matematika GASING. Almost all thought that the learning was easy, fun and enjoyable. Students’ ability to do mental subtraction after a learning with Matematika GASING was also investigated. The mastery level achieved in the mental subtraction test taken after the learning was 76% (also an improvement from the test taken at preliminary study).

Keywords: basic mathematics, mental subtraction, subtraction, Matematika GASING