The training program of the 3rd graders in Kure National College of Technology has been focused on re-learning electrical theories and learning the ways to use electrical equipment. In 2012, we changed the existing training program into something more focused on fostering young engineers’ manufacturing skills. Then, we developed a microcomputer educational tool which includes a liquid crystal display, a long distance measuring sensor and two 8x8 dots matrix displays as the chief requisite of the practical training. In this tool, the difficult part of programs (ex. Initializing and I/O setting) are encapsulated for the 3rd graders who are unskilled in these programs. In this paper, we report and discuss the educational effect of using these original educational tools.