Implementation of science technology engineering and mathematics approach in learning to critical thinking skills of fifth-grade elementary school students in Lampung Province

The type of research used is experimental research. Experimental research is that researchers deliberately make experimental research and there are controls and conditions regulated by researchers (Triyono, 2013). The research method used is a quasi-experimental design (Sugiyono, 2015). The variables contained in this study consisted of two independent variables (STEM approach) and the dependent variable (critical thinking skills).

The fifth-grade of Tri Sukses Natar elementary school is selected as experimental and non-experimental classes. The experimental class (n = 29 students) uses the STEM approach, while the non-experimental class (n = 30 students) doesn’t use the STEM approach. Then, the experimental and non-experimental classes is assessed and compared to see the cause and effect and its effect on the variables given the treatment. Critical thinking skills data is measured using a test instrument. The test refers to an indicator of critical thinking skills known as FRISCO (Davies & Barnett, 2015; Ennis, 2011).

Based on the indicators of critical thinking skills, the authors made six test questions in the form of essays to measure the critical thinking skills of fifth-grade students. The questions are made according to the indicators of critical thinking skills which consist of FRISCO. Previously, the author perform the instrument test on 22 students at Gedong Air 1 elementary school who have the same criteria as the students of elementary school where the main research is conducted. The six questions is declared valid and reliable with the acquisition of r count > r table. Test the validity of the test instrument using the product moment correlation formula, while the reliability test using the Cronbach Alpha formula (Fraenkel et al., 2012).

It is adjusted to the four aspects of STEM i.e., science, technology, engineering, and mathematics (Guleryuz & Dilber, 2021). Aspects of science are focus learning on shape of objects and force of gravity of the earth which is associated with the subject matter of building cubes and blocks. The students learning outcomes for this aspect are students know and understand that a cube and block is an example of a solid object. The technological aspect is to direct students to apply the knowledge gained into a skill using hardware such as laptops and smartphones to get information that will be useful for designing a product to be produced. This is raised in learning by showing videos about building cubes and blocks using an LCD/projector and laptop.

Following the next aspect is engineering used to trained students to be able in processing and to solve existing problems such as how to design products accurately on it size (Shahali et al., 2017). For example, students make a dice design with the concept of building a cube space and make a pencil box design with the concept of a unit cube. When carrying out engineering aspects in learning, students can indirectly construct their thoughts in designing a project related to their life and also create creativity and improve critical thinking skills. The last for mathematical aspect, student is directed to gain the basic competencies and indicators in learning achievement of fifth-grade that is to analyze the elements of building blocks and cubes. The results are that students become easier to understand the learning of building cubes and blocks, seem more fun by making a project and think logically (Han et al., 2016).

Based on those aspects, the authors started to give pre-test before implementing the STEM approach. So that, the authors treat STEM to the students and at the end of the lesson the authors give a post test to see the results of the STEM approach treatment (Sugiyono, 2015) (see table 1).

Table 1. The procedure of a quasi-experimental design.

O1	X1	O2
O3	X2	O4

Note:

O1 = Pre-test value in the experimental class,
O2 = Post-test value in the experimental class,
O3 = Pre-test value in the non-experimental class,
O4 = Post-test value in the non-experimental class,
X1 = Treatment using the STEM approach,
X2 = Treatment without using the STEM approach.

Then the normality test is calculated using the following Kolmogorov Smirnov formula (Razali & Wah, 2011).