this chapter, the review of literature begins with the definition of scientific inquiry and the development of standards in science. Literature concerning the use of inquiry as a teaching strategy and process are reviewed. Research on student assessment will also be reviewed, providing the background of how inquiry based learning affects student achievement and attitudes towards science. Finally, in this chapter, is a review of research concerning science teacher’s professional development and the use of inquiry in the process. It is the intent of this chapter to develop a rationale for further study of the effects of inquiry-based learning on student achievement.According to the National Science Education Standards inquiry based science is a multifaceted activity (National Research Council 1996). It is based on specific teaching styles and curriculum that requires students to work together to solve problems rather than receiving direct instructions on what to do from the teacher. Teachers should be facilitators of student learning instead of someone who simply lectures facts out of a text book. The National Science Education Standards, published in 1995, explains what it means to be scientifically literate, describing what all students should understand and be able to do at different grade levels in general science categories. The National Science Education Standards encourages science teaching that provides students with experiences that enable them to achieve scientific literacy. In regards to classroom instruction, Chiappetta (1997) suggests that a classroom be an exciting learning environment where students are asking questions, resolving discrepancies, figuring our patterns, representing ideas and solving problems. Two approaches to inquiry are explained, one is that science is taught by inquiry and the other where science is taught asinquiry. Science by inquiry or sometimes referred to as “learning by discovery” is finding out about everything and anything. With this style of teaching students attitudes and critical thinking skills are emphasized. Teaching science asinquiry stresses the importance of understanding a scientific concept and the importance of active student learning. Science content becomes the critical piece when teaching science asinquiry.The key components to programs that promote student inquiry as identified by Edwards (1997) include keeping the focus on real-life experiences of the students. He points out that when examining current science curriculum whose primary aim is inquiry, a basic flaw is revealed, students aren’t formulating questions creating and testing hypotheses to answer proposed questions.In a review of hands on science experiences by Stohr (1996), the correlation between student achievement and frequency of hands on experience was discussed. A random sampling of schools from across the country resulted in a sample of 24,599 8th grade students from 1052 different schools. Data was collected into groups based on the amount of hands-on science activity students were exposed to, i.e. every day, once a week, once a month, less than once a month, and never. The results of the t-test indicated that the eighth grade students who experienced hands-on activities either every day or once a week scored significantly higher than those who participated once a month or less.Schools are feeling the push to improve science achievement levels and the quality of teaching. The need for accountability and proof that students are meeting desired outcomes is critical to student achievement on standardized tests. In a four-year study from 1995 – 1999, Klentschy, Garrison, and Amaral (1999) compared the use of kit-based science instruction and student achievement in schools in the Valle Imperial Project in California. Results indicate that the longer students were in the program, the higher their scores in science, writing, reading, and mathematics. The students in selected pilot schools used four kits per year in grades 1-5 and three kits in kindergarten. The hands on activities allowed students to build an in-depth knowledge in the subject matter. The results of the study were favorable towards the kit-based instruction in general and noted specific improvement for females, economically disadvantaged, and minority students.Schmidt (1999), describes how teachers in grades K-5 followed an inquiry learning and teaching approach, called KWLQ, what I know, what I want to know, what I learned and any additional questions there may be. In this study, students recorded their prior knowledge, formulated questions, searched for answers, and generated hypotheses that could be tested. Students were able to locate new information and data, answer their own questions about the natural world, and solve problems with an appropriate level of assistance from the teacher using the KWLQ technique.Another area of interest related to inquiry-based science instruction is the relationship between an inquiry-based science programs and its relation to students’ attitudes towards science. Gibson (1998) evaluated the impact of the Summer Science Exploration Program (SSEP) at Hampshire College in Amherst, MA. Over one hundred fifty students were randomly selected to participate in the program from 1992 to 1994. Following the summer program seventy nine SSEP students were asked to complete two quantitative surveys. For comparison, thirty five students who applied to the program, but were not selected, also completed the two surveys. Pre and post test scores were analyzed and suggest that SSEP may have helped those students maintain a positive attitude towards science and higher interest in science careers compared to those who were not selected to participate, suggesting that inquiry based science programs may have a positive impact on student attitudes.?In order for inquiry based science to be successful in the classroom teachers need to have a deep understanding of the subject matter. Loucks-Horsley et al. (1998) reviewed several professional learning strategies and determined the strategy entitled Immersion in Inquiry into Science and Mathematics as an effective way for teachers to develop awareness, build knowledge, and to reflect. The review suggests the findings of the program to be beneficial, but indicates potential drawbacks with limited teacher time and resources.In a National Science Teachers Association (NSTA) Position Statement, science teachers recognize the value of staff development and collegial efforts to provide meaningful learning achieve “the most meaningful science learning experience for students…. Teacher training and professional development programs must promote and help teachers work toward coordination for student achievement and quality teacher retention” (2000, p 1).A research study by Martinello (1997) surveyed graduates from an elementary teacher education program to assess how they viewed the success of the program and its goals. The study showed that 64% thought the program helped them to become self directed learners, 70% believed that the program helped them to understand how knowledge is discovered, invented, and 75% said the program help them to see connections between other fields of study. For students who have just completed student teaching and graduated from a teacher specific program, the percentages are low. Martinello believes the key to successful teacher use of inquiry and exploration is the ability for students to improve hypotheses and to take varied perspectives on the problem. How can teachers be expected to implement standards-based instruction using inquiry if they have not been trained accordingly?The ongoing debate between inquiry based learning and traditional instruction is the reason this study must take place. If inquiry methods truly are more effective, then it is critical for teachers to be given the training, support, time, and resources necessary to implement them in the classroom. If, however, traditional methods are just as effective, then other teaching approaches should be considered and reform efforts should be refocused.