1. [1] Programming Education at the Elementary School, available from <https://www.mext.go.jp/b_menu/shingi/chousa/shotou/122/attach/137-2525.htm>.
2. [2] Cruz, I., Amali, W. and Cheryl, P.: A study of code design skills in novice programmers using the SOLOtaxonomy, ICER, pp.25-259 (2016).
3. [3] Matsumoto, S., Kashima, T. and Yamagishi, S.: An analysis of the relationship between the level of understanding of programming games played before learning programming and its achievement after learning, Information Education, Vol.2, pp.31-40 (2020).
4. [4] Prensky, M.: Digital Game Learning, Tokyo Denki University Press, pp.162-229 (2009).
5. [5] Lai, A. and Yang, S.: The learning effect of visualized programming learning on 6th graders' problem solving and logical reasoning abilities, ICECE (2011).