Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisor: Fred Valdez, Jr. Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Includes vita. Includes bibliographical references: (p. 322-336).

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The purpose of this study is to determine what opportunities the public schools of the Lower Rio Grande Valley of Texas are offering to Latin-American students, how they are meeting the students' needs, and what changes, if any, could be made to adjust their curriculum to meet these needs.

The focus of this study is the economic feasibility of drip irrigation adoption using capital budgeting and quadratic programming techniques. The capital budgeting techniques used in the study are net present value (NPV) and returns above specified costs (RASC). Modified crop enterprise budgets incorporating drip irrigation are developed based on data from Texas AgriLife Extension Service crop enterprise budgets and published literature focusing on costs and returns of drip irrigation. The quadratic programming technique considers risk and incorporates the modified crop enterprise budgets to estimate a cropping pattern that maximizes the net income above specified costs for the region. The RASC per acre for drip-irrigated crops ranged from $56.34 to $1,909.03, while the RASC per acre for flood-irrigated crops ranged from $142.51 to $1,488.12. Flood-irrigated onions, cotton, and sugarcane had higher RASCs per acre, while the RASCs were greater for drip-irrigated grapefruit and oranges. Evaluating the NPV of the crops resulted in similar results; only grapefruit and oranges were economically-feasible drip-irrigated crops. The baseline results identified levels of drip irrigation adoption ranging from 52,000 acres to 64,497 acres as levels of risk were varied. The level of water available at the reservoir suggested minimal impacts on the level of drip-irrigation adoption, but serious implications for the agriculture economy. Several sensitivity scenarios concentrated on the implications of yield response and water savings that result from the adoption of drip irrigation. The greatest amounts of drip-irrigated crops were present when the yield responses were 130% of the flood-irrigated crops with a 20% water savings. As the amount of water available was reduced, the amount of drip-irrigated crops ranged from 46,111 acres to 59,724 acres. Drip irrigation appears to be an economically-viable alternative in the LRGV due to the presence of drip-irrigated crops in the entire myriad of scenarios investigated in this research. If producers are only concerned with the bottom line as provided by the RASC analysis and no other variables such as water availability, risk, and crop rotations affecting the decision making process, only drip-irrigated grapefruit and oranges are economically competitive with conventional irrigation systems.

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This study examined how higher performing middle schools in the Rio Grande Valley use data to drive instructional decisions. Three research questions guided this study: (a) to what extent do higher performing, Title-1, middle schools in the Rio Grande Valley utilize data to make schoolwide instructional decisions; (b) how does the principal support data use for instructional decision-making; and (c) what do teachers perceive to be the processes that have led to the current level of data use in instructional decision making? A mixed-methods multiple-case study included middle schools that were drawn from a list of higher performing schools according to Just for the Kids and the National Center for Educational Achievement. To be included in the study, schools had to be located in the Rio Grande Valley, Texas, specifically in the counties of Starr, Cameron or Hidalgo. Additionally, the schools needed to be designated a Title-1 school, according to federal criteria. Data for the study was collected using a survey, followed by one-on-one interviews. Descriptive analyses was then conducted using the survey data. The interview data was analyzed using first-level coding followed by the use of cross case analysis to determine themes common to all cases. The findings from this research revealed that data is used extensively in the schools studied; primarily to determine the instructional scope of what is taught. It was found that while data use was extensive, the source and purpose of data use was limited to that which was directly tied to the state-administered assessment (TAKS). The second major finding was that principals create the necessary conditions for data use that becomes an embedded practice, where teachers can take risks with their colleagues in reviewing and using data. This study concludes that more principals can lead their schools to greater levels of data use by creating the necessary conditions for change. At the same time, the findings suggest that there is a need for leaders at all levels to examine and mitigate the unintended consequences of data use that is derived from a single-source and for a single purpose—that is, performance on the state exam (TAKS). / text

It is the purpose of this study to consider the Anglo-American child--to examine his achievement in a situation where much consideration will of necessity be given to the instructional needs peculiar to the predominating group.