Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Agricultural Education and Studies


The purpose of this study was to evaluate the impact of an instructional packet on supervised occupational experience programs in terms of student agricultural knowledge achievement after two and one-half years. The study was a posttest only control group (true experimental) design. Students (in 16 schools that had been randomly assigned to the experimental treatment group) provided data for comparison with data from students in the 16 schools that were similarly assigned to the control treatment group. The "experimental treatment" consisted of access to (and inservice instruction for teachers in the use of) an instructional packet developed to help beginning students select and plan individual SOE programs. The control group teachers taught their "normal" instructional units on SOE to their beginning classes;Four instruments were used to evaluate the effectiveness of the instructional packet: an Involvement in Agriculture Inventory and the Animal Science, Plant and Soil Science, and Mechanics subtests of the Agribusiness Achievement Test. Previously acquired data concerning student SOE knowledge, attitude, and planning were used in the analysis of data. Data analysis procedures employed included: frequencies and counts, student's t-test of mean differences, analysis of variance, and Duncan's Multiple Range Test for Mean Differences;Major findings of the study were: (1) The SOE packet was effective in helping students achieve, (2) SOE is an effective teaching method, (3) The primary types of SOE possessed by juniors observed in Iowa (ownership of animals/crops, work on farms other than home, work in off-farm agribusiness, and school projects other than normal classroom and shop activities) comprised 95% of reported SOE participation, (4) these Iowa juniors have achieved significantly more agricultural knowledge than their 1972 national counterparts, (5) Students achieved more knowledge in mechanics and animal science than in plant and soil science, (6) Teacher stability (whether in 1978 teacher continued to teach at that school) had no significant impact on the knowledge achievement of students, and (7) Beginning student knowledge of SOE (after instruction in the freshman year of vocational agriculture) was determined to be a reliable predictor of student knowledge achievement for those students as juniors two and one-half years later.



Digital Repository @ Iowa State University,

Copyright Owner

John Wilbur Jones, Jr.



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104 pages