Studied the reliability and validity of the Visualizer/Verbalizer Behavior Observation Scale (VV-BOS), a computer-based instrument for direct observation of students' preferences for visual or verbal learning material, in an authentic training situation. 103 Californian college students (mean age: 21.9 years) enrolled in second-year German language courses completed the Edmonds Learning Style Identification Exercise (ELSIE) and the Visualizer Verbalizer Questionnaire (VVQ). They then performed the VV-BOS, which is embedded within the multimedia learning program CyberBuch. Finally, they performed a comprehension test and a vocabulary test. Results showed that the VV-BOS had an exceptionally high internal consistency of .92 and a high parallel test correlation of .75. Validities assessed through correlations with ELSIE and VVQ were somewhat inconsistent. When all 3 instruments were used to predict learning outcomes, only the VV-BOS predicted aptitude-by-treatment interactions successfully. It is concluded that the VV-BOS offers a promising alternative to traditional questionnaires.