The purpose of this study was to explore the effects of the context-aware ubiquitous learning (u-learning) approach versus traditional instruction on students' ability to answer questions that required different cognitive skills, using the framework of Bloom's taxonomy of educational objectives, including knowledge, comprehension, application, analysis, and synthesis. In this study, 230 third- and fourth-grade students in 8 classes were counterbalanced and assigned to the u-learning approach and traditional instruction for learning different topics in two separate plant-observing activities. The results showed that the students who learned with traditional instruction performed better than those who used the u-learning approach in terms of answering questions that required their cognitive abilities of knowledge, comprehension, application, analysis, and synthesis. Moreover, an in-depth analysis of the students' learning behaviors in the u-learning context revealed that most of their learning behaviors recorded in the u-learning system were not significantly related to their cognitive abilities.