This research aims to find out how effective the IoT microcontroller training kit learning media is and to analyze the effect of using the IoT microcontroller training kit compared to the common microcontroller training kit on students' cognitive learning outcomes in learning microcontroller and microprocessor programming techniques. The normalized gain method was used to determine the effectiveness of the IoT microcontroller training kit learning media. The ANOVA method was used to determine the effect of using the IoT microcontroller training kit and common microcontroller training kit on the average student cognitive learning outcomes. The research results show that the IoT microcontroller training kit learning media has a normalized gain value of 59.62% in the effective enough category. The average cognitive learning outcomes of students using the IoT microcontroller training kit are greater than those using the regular microcontroller training kit, according to the results of the study using one-way ANOVA, where the p-value is less than the α value of 0.05. This IoT microcontroller training kit can be used to improve students' cognition regarding microcontroller learning in vocational schools.