A comparison of VRML and animation of rotation for teaching 3-dimensional crystal lattice structures.

Chemistry students often have difficulty visualizing abstract concepts of molecules and atoms, which may lead to misconceptions. The three-dimensionality of these structures presents a challenge to educators. Typical methods of teaching include text with two-dimensional graphics and structural models. Improved methods to allow visualization of 3D structures may improve learning of these concepts.;This research compared the use of Virtual Reality Modeling Language (VRML) and animation of rotation for teaching three-dimensional structures. VRML allows full control of objects by altering angle, size, rotation, and provides the ability to zoom into and through objects. Animations may only be stopped, restarted and replayed. A web-based lesson teaching basic concepts of crystals, which requires comprehension of their three-dimensional structure was given to 100 freshmen chemistry students. Students were stratified by gender then randomly to one of two lessons, which were identical except for the multimedia method used to show the lattices and unit cells. One method required exploration of the structures using VRML, the other provided animations of the same structures rotating. The students worked through an examination as the lesson progressed.;A Welch t' test was used to compare differences between groups. No significant difference in mean achievement was found between the two methods, between genders, or within gender. There was no significant difference in mean total SAT in the animation and VRML group. Total time on task had no significant difference nor did enjoyment of the lesson. Students, however, spent 14% less time maneuvering VRML structures than viewing the animations of rotation.;Neither method proved superior for presenting three-dimensional information. The students spent less time maneuvering the VRML structures with no difference in mean score so the use of VRML may be more efficient. The investigator noted some manipulation difficulties using VRML to rotate structures. Some students had difficulty obtaining the correct angle required to properly interpret spatial relationships. This led to frustration and caused some students to quit trying before they could answer questions fully. Even though there were some difficulties, outcomes were not affected. Higher scores, however, may have been achieved had the students been proficient in VRML maneuvering.