Comparative study of two groups of engineering students, one from the United States and one from Thailand, was conducted. Their performance and their behavior were compared to show the differences or similarities that may not be obvious when only a few students from one group is placed with the other group, i.e., foreign students in a US classroom situation. The US sample group was from solid mechanics classes taught at the University of Utah, USA from 1994 to 1997. The Thailand group was from the solid mechanics classes taught at Sirindhorn International Institute of Technology (SIIT), Thailand from 2001 to 2004. Both groups were subjected to similar teaching and learning conditions. It was found that the Utah group performed better than the SIIT group in all grading categories, i.e., assignment, exam, and project. The differences can be attribute to the age, level of expectation, and cultural conditioning. Understanding the root causes of the differences in performance of the two groups can help US-base engineering educators deal with "foreign" students more effectively.