3.4 Data collection-Techniques, Procedure
3.4.1 The researcher gave a questionnaire, pre-test to sample groups. Since class size at Saint Gabriel’s College primary 6/1, 6/2, and 6/4 students are limited to 10 students in a class and in order to identify with the application of Thai folk song in learning Thai language improved students’ attitude, teaching strategy, and teachers’ competency the most, the researcher made the sample for control group into one where each group had 10 students totaling to three groups. The control group was used.