Semantic scaffolds in hypermedia learning environments

In knowledge acquisition from hypermedia, learners have to orient themselves in a non-linear information space, navigate in this space and build a knowledge structure from the information there. Research on learning from hypermedia has focused primarily on enhancing orientation and navigation, with only minor attention on possibilities for supporting semantic processing. In a first experiment, 98 students from senior high school and university undergraduates learned about a complex subject matter either without or with semantic scaffolds, which were presented either in an obligatory (non-removable) or in an optional mode. High prior knowledge learners profited from adequately used semantic scaffolds, whereas low prior knowledge learners did not. In a second experiment, 53 senior high school students and university undergraduates received the learning material with semantic scaffolds presented either in an obligatory mode (but removable on demand) or in an optional mode. Learners with low prior knowledge performed better with optional presentation. Learners with high prior knowledge performed better with obligatory presentation, which allowed removing scaffolds on demand. Learners generally preferred the optional presentation of learning scaffolds.