Abstract: This current study used three experiments to examine the learning effects of prior knowledge and concept map types on learning scientific expository essays, as well as how to promote learners with low prior knowledge to learn scientific expository essays by interactive concept maps. In Experiment 1, the impact of learning with different types of concept maps was investigated for learners with high and low prior knowledge. In Experiments 2 and 3, we investigated whether adding text before learning interactive concept maps and interactive concept maps with hierarchical structure might effectively promote the learning effect of learners with low prior knowledge. The results showed that: (1) For learners with high prior knowledge, learning scientific expository essays by interactive concept maps has a better transfer effect than learning them by static concept maps, and both static concept maps and interactive concept maps had better retention effects. For learners with low prior knowledge, the transfer effect of learning by static concept map was better than that of interactive concept map, and the retention effect of learning by static concept map was better than that of connecting interactive concept map; (2) Learners with low prior knowledge who read relevant texts prior to studying interactive concept maps performed significantly better on both retention and transfer tests than those who did not; (3) Learners with low prior knowledge learned better from hierarchical structure concept maps than from network structure concept maps on both retention and transfer performance. The findings indicate that learners' prior knowledge and concept map type affect the learning effect of scientific expository essays. For students with low prior knowledge, both the inclusion of relevant texts and the use of hierarchical concept maps can effectively improve the learning effect of scientific expository essays through interactive concept maps.

Key words: scientific expository essays, prior knowledge, static concept maps, interactive concept maps