Like most country schools in Taiwan, the scale of the elementary school is small. Its total student population is 88. The participants of this study are 13 fifth-grade students taught by the same teacher. The ages of the participants range from 10 to 11 and their average age is
10.76. After receiving the fundamental plant knowledge in their natural science course, the participants were randomly divided into a control group (n= 6) and an experimental group (n= 7).