PlantingScience (PS) is a unique web-based learning system designed to develop secondary students' scientific practices and proficiencies as they engage in hands-on classroom investigations while being mentored online by a scientist. Some students' teachers had the opportunity to attend PS professional development (PD). In this dissertation, I developed a process of assessing student learning outcomes associated with their use of this system and evaluated inquiry engagement within this system. First, I developed a valid and reliable instrument (Online Elements of Inquiry Checklist; OEIC) to measure participants' (students, scientists, and teachers) engagement in scientific practices and proficiencies embedded within an inquiry cycle I collaborated with an expert-group to establish the OEIC's construct and content validities. An inter-rater reliability coefficient of 0.92 was established by scientists and a split half analysis was used to determine the instruments' internal consistency (Spearman-Brown coefficient of 0.96). Next, I used the OEIC to evaluate inquiry cycle engagement by the participants who used the PS online platform designed by the Botanical Society of America which facilitated communication between participants. Students provided more evidence of engagement in the earlier phases of an inquiry cycle. Scientists showed a similar trend but emphasized experimental design and procedures. Teachers rarely engaged online. Exemplary students' outcomes followed similar inquiry cycle trends, but with more evidence of engagement with one notable difference. Exemplary students provided evidence for extensive engagement in immersion activities, implicating immersion as a crucial component of successful inquiry cycle engagement. I also compared engagement outcomes of students whose teachers attended the PD experience to the students of teachers who did not attend PD. Differences found between the two groups occurred throughout the inquiry cycle, typically associated with experiences provided during the PD. As a result of this research I have several recommendations about revisions to the PS online platform and use of approaches to assure students development of scientific practices and proficiencies. The recommendations include additional scaffolding of the platform, explicit inquiry cycle instruction, and continued opportunities for teachers to engage in PD experiences provided by PS.

The purpose of this study was to better understand student learning in asynchronous computer-conference discourse (ASD) for non-native speakers of English in India through the Community of Inquiry (COI) framework. The study looked at ASD from an online course taught in the fall of 2015 to 25 students in a seminary in South India. All but one of the students were non-native speakers of English. The class consisted of 22 men and 3 women. Eight students spoke languages from the Dravidian family of languages (Malayalam, Tamil, Telegu and Kannada). Eight students were from the Northeastern states of Manipur, Nagaland and Tripura, where most languages are from the Sino-Tibetan family. Three students were native speakers of Indo-Aryan languages (Odiya and Assamese). Five students were from Myanmar representing several Sino-Tibetan languages. The COI is a framework used to understand learning in ASD, often used in online learning. To study the ASD of this group, critical discourse analysis (CDA) was used with the COI to capture the unique socio-cultural and linguistic conditions of this group. The study revealed that non-native speakers of English often reach the Exploration phase of learning but rarely show evidence of reaching the Resolution phase. This phenomenon was also observed in native English speakers as reported in the literature. Also, the structure of ASD showed that students took an examination approach to discussion shaped in part by their epistemology. This examination approach shaped how knowledge was constructed. CDA also showed that the discourse acquired an instructor-centered structure in which Resolution and Repair were initiated and finalized by the instructor. The study advances the COI framework by undergirding it with a theory of asynchronous discourse using critical discourse analysis and capturing cognitive, social and teaching presence phenomena for non-native speakers that were not observed through the traditional COI framework. These phenomena were driven by cultural, epistemological, and linguistic forces and require a rethinking of the COI for contexts outside of North America. The study also demonstrates that learning for non-native speakers in ASD is challenged by these very same forces. Therefore, design for online learning should account for these phenomena.