We have developed teaching materials to be used in the study of “The Structure and Function of the Animal Body” by second grade students of junior high school. In this course, students learn about the anatomy of animals and humans but cannot directly observe it. The textbooks only cover the anatomy of the squid, and it is difficult for students to compare it to that of the human. Therefore, we developed a human heart model as teaching materials to enable students to learn through actual interaction. In class practice, multiple students can operate the model at the same time, allowing for exploratory learning through trial and error. By actually manipulating the heart model, the students were able to gain a concrete view of the structure of the heart and how it works. According to the questionnaire-based survey after the class, 97% of the students answered positively that the use of the heart model helped their learning, and the majority of the students felt that the model was effective. This study suggests that the use of the cardiac model allows students to learn in an exploratory manner, rather than by being given knowledge passively.

Since fine bones are not lost during the making process and the three-dimensional structure is preserved in the original state, the transparent skeleton specimen is suitable for observing the skeleton in science class. However, making this specimen requires a chemical legally designated as a poisonous or deleterious substance. Xylene used for degreasing and acetic acid for tissue fixation have a strong odor and often make students feel sick. Teachers may hesitate to prepare transparent skeleton specimens because of such safety issues and impaired comfort. In this experiment we show a method for preparing transparent skeletal specimens without using such substances. Specifically, the fish after fixing with 70% alcohol is soaked in a laundry detergent at 30°C for 10 days, stained with a 30 μg/mL Alizarin Red S aqueous solution for 2 hours, and then transferred to glycerin. In class practice, students were able to make more than a dozen types of fish specimens other than goldfish, which shows the possibility that this method can be applied to the preparation of transparent skeleton specimens in many fish species. Our study will accelerate the introduction of transparent skeletal specimens in class and inquiry activities.