A team of engineering and education faculty and science education graduate students partnered with a local high school to implement an engineering design course. Course objectives included: learning to apply the engineering design methodology, acquiring and using basic engineering skills and tools, and understanding and valuing engineering as a career and a profession. The objectives were generally not achieved due to a variety of barriers related to the class. These included: varying maturity levels of students due to mixed age groups; lack of diversity; need for enhanced structuring of classes; inappropriate placement of students in engineering classes by guidance counselors; issues of materials management; inadequate application of science and math in design and problem solving; and the level of difficulty of course books. The nature of these barriers is discussed along with implications for teaching engineering design in high school. Recommendations for improvements to fulfill course objectives and achieve learning outcomes are presented.