Amarit P.Longpradit P.Mahidol University2026-04-132026-04-132025-07-01Kasetsart Journal of Social Sciences Vol.46 No.3 (2025)https://repository.li.mahidol.ac.th/handle/123456789/116183The objective of this mixed methods research was to develop and evaluate a 21st century skills training module for private preschool teachers that contained facilitation skills development and a microlearning-based follow-up support toolkit. In the first phase, data were collected via focus group discussion with 8 experts purposively sampled with these selection criteria: at least 5 years of experience; fields of expertise: facilitation; 21st century skills training; monitoring and evaluation; preschool education, and parenting. Data were analyzed via content analysis. The results were used to develop the training module. In the second phase, data were collected via quasi-experiment with 20 participants sampled via multistage random sampling from 30 schools and purposively sampled into the control and experimental groups – the selection criteria being the participants’ own choice. Demographics included: 13 preschool teachers and 7 teacher assistants – all female – with at least 2 years of experience. Data were analyzed via descriptive and inferential statistics – t-test. The results showed significance from the pretest (average M: 3.88; average SD: 0.83) to the posttest (average M: 4.43; average SD: 0.73) in terms of achievement, which improved through facilitation skills development; the results also showed significance when comparing acceptance of the experimental group (average M: 4.44; average SD: 0.73) to the control group (average M: 3.22; average SD: 0.96), which was through follow-up support. The contribution of this research recommended utilizing both facilitation skills development and follow-up support for 21st century skills workshops.Social SciencesArticleSCOPUS10.34044/j.kjss.2025.46.3.162-s2.0-10503427551124523151