Aspiring secondary school science teachers must experientially learn the way of using a telescope and teaching star watching through a stargazing session. As a part of experiential activities, a stargazing session to observe the moon and Saturn was organized for 5-year-old kindergarten children on October 27, 2017, by graduate and undergraduate students; the session was conducted on the roof of building C of the Faculty of Education, Hiroshima University. The preparation for the session was a good opportunity for the students to review the knowledge that they had learned in class. The students interviewed the children about the shape of moon and Saturn immediately after they observed the planets. The two kinds of telescope used in star observing and the order of the planets that the children watched did not have much effect on the visibility of the planets. The results of interviews on the shape of the Moon indicated that the children understood the rough shape of the moon; however, they could not make an accurate understanding of the difference of the shape on the right and left sides. Furthermore, a possible effect of visual information, such as drawings, on the form of stars was confirmed.