As the emphasis on accountability in education increases, so does the prevalence of low-stakes testing. It is essential to understand test-taking motivation in low-stakes contexts, as low motivation has implications for the validity of inferences made from test scores about examinee knowledge and ability. The current study expanded upon previous work by exploring the existence of types of test-takers characterized by qualitatively distinct patterns of test-taking effort across the course of a three-hour low-stakes testing session. Mixture modeling results did not support the existence of types of test-takers for this sample of upperclass examinees. Latent growth modeling results indicated that change in effort across the testing session was well-represented by a piecewise growth form, wherein effort increased from the first to fourth test and then decreased from the fourth to fifth test. Further, there was significant variability in effort for each test as well as in rates of change in effort. The inclusion of external predictor variables indicated that whether an examinee attended the regular testing session versus a make-up session, mastery approach goal orientation, conscientiousness, and agreeableness partly accounted for variability in effort for the various tests, whereas only agreeableness was related to rates of change in effort. Additionally, the degree to which examinees viewed a particular test as important was weakly to moderately related to effort for a difficult, cognitive test but not for less difficult, noncognitive tests. Further, change in test-taking effort was not related to change in perceived test importance. These results have important implications both for assessment practice and the use of motivation theories to understand test-taking motivation. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]