One of the major problems that students experience while studying is that they are not aware of what they are learning or what they are doing. Students have many difficulties in managing time, choosing effective learning strategies, and preparing for tests (Zimmerman, Bonner & Kovach, 1996). Zimmerman (2002) developed a model in which he defined self-regulation as "self directive process by which learners transform their mental abilities into academic skills" (p.65). He explains the function of self-regulatory processes in learning with three cyclic phases. These processes help students motivate and guide their own learning. The first phase, forethought phase, includes processes preparing students for learning. After evaluating their initial level, students set their own learning goals and determine which strategy to use. The second one, performance phase, includes the implementation of strategies for learning and monitoring their accuracy. The third phase, self-reflection phase, consists of processes that occur after learning. Students judge what they have learnt and what they need to learn. Self-reflection phase is followed by the forethought phase of the next learning process.The purpose of this study was to develop and validate a scale assessing self-regulatory strategies that high school students use while studying for chemistry class. A valid and reliable self-regulatory strategies scale would make a significant contribution to chemistry education. Students' self-regulatory skills must be considered in choosing appropriate instructional approaches in order to promote student achievement (Zimmerman & Bandura, 1994).An initial pool of 61 items was generated based on interviews conducted with high school students (Kadioglu et al., 2006), Zimmerman's self-regulation model, existing self-regulation instruments, and expert opinions. After receiving feedback from various colleagues and subject-matter experts, the number of items was reduced to 46. Items were formatted on a six-point rating scale of frequency ranging from "never" to "always." Resulting self-regulation scale was administered to 422 tenth grade students. Because the main purpose of this study was to construct a multidimensional measure of self-regulation, an exploratory factor analysis was conducted using maximum likelihood method of extraction and direct oblimin rotation to allow for correlations among factors.A variety of criteria was used to determine the number of common factors to retain: the eigenvalue greater than 1 criterion, the scree test, the amount of common variance explained, and conceptual interpretability of the factor structure. These criteria suggested the adequacy of extracting eight factors, accounting for 60% of the common variance. The factors were labeled: help seeking, motivation regulation, effort regulation, planning, attention focusing, task strategies, additional resources, self-instruction. In regard to the item selection, factor loadings of 0.40 were higher were considered meaningful. Eight items with low factor loadings were excluded. In addition, Cronbach's alpha was calculated to determine the internal consistency of the self-regulation items. Results indicated that the self-regulation scale overall had high internal consistency (0.91). Eight of the subscales obtained in the factor analysis also had adequate internal consistency, ranging from 0.69 to 0.82.Results of this study indicate that the self-regulation scale is a valid and reliable tool for studying high school students' self-regulatory strategies while studying for chemistry. Factor analysis supported the claim that self-regulation is a multidimensional construct consisting of different processes. This scale was tested with only chemistry students; however the scale may be a potentially useful tool in other disciplines related to science. Kadioglu, C., Uzuntiryaki, E. & Capa Aydin, Y. (2006, September). A Qualitative Study on Tenth Grade Students' Self-Regulatory Skills. VII. National Science and Mathematics Education Conference, Gazi University, Ankara:Turkey Zimmerman, B. J. (2002). Becoming a Self-Regulated Learner: An Overview. Theory into Practice, 41(2), 64-70. Zimmerman, B. J., & Bandura, A. (1994). Impact of self-regulatory influences on writing course attainment. American Educational Research Journal, 31, 845-862. Zimmerman, B. J., Bonner, S.& Kovach R. (1996). Developing self-regulated learners: Beyond achievement to self-efficacy. Washington: APA.