What advanced 4- and 5-year-old children know about night and day in relationship to the earth and sun was studied to test the hypothesis that two teaching activities would help children to understand the cause of the phenomenon. Participants were 21 middle to upper class boys and girls enrolled in a part-time early childhood enrichment program offered at a university. Most subjects were gifted. Two groups were formed of students enrolling in the program at different times; one student was enrolled in both groups. Group A was taught earth and sun concepts through the use of a role-playing activity. Group B was taught through the use of a globe and flashlight. Students were interviewed before and after instruction to ascertain their understanding of the earth and sun as well as to determine the effect the activities had upon their learning. Over half of the subjects made gains in understanding the concepts. Results from both groups were similar, with slightly more positive gains being achieved by Group A students. The students in both groups revealed increased understanding in the interviews following both types of instruction. It was concluded that these results dispute past studies claiming that earth and sun concepts are too abstract for young children to understand. Most students learned the concepts. However, it appeared that the relationship between the concepts is very difficult for young students to understand. (RH)