I’m not saying that’s the only reason. High school preparation is certainly the most important, especially in non-selective schools. I was referring to loss of prepared students and the rise of “hands on” programs.
The first lines of the discussion in the paper cited above are:
“As any experienced engineering educator knows, some engineering students leave because they discover a passion for a discipline other than engineering—it is hard to argue that we should be trying to prevent such students from leaving. However, it is also true that a significant proportion of engineering students leave because the engineering educational system has failed to show them that the engineering endeavor is profoundly human, has failed to make relevant the key scientific, mathematical, and engineering principles needed for mastery of engineering, has failed to show that engineering is within reach of their abilities, has failed to capture their imagination and fascination, and has failed to provide a welcoming atmosphere to them.”
https://www.rise.hs.iastate.edu/projects/CBiRC/IJEE-WhyTheyLeave.pdf
“Other studies have shown that a primary reason for the attrition of students from engineering is their perception of a learning environment that fails to motivate them and is unwelcoming; it is neither the students’ capabilities nor their potential for performing well as engineers that determines their persistence[3].”
Unfortunately, I can’t link the original citation anymore. The Google seems to have lost it.
https://www.asee.org/retention-project
“Research shows that the first two years are often crucial to student retention and eventual success. In addition, lecture courses generally have been found to be less effective than active learning.”
https://www.asee.org/retention-project/keeping-students-in-engineering-a-research-guide-to-improving-retention
I read the findings of the ASEE Retention Project when my son was still in HS. Given his preparation, I concluded that the only real possibility of my him dropping out of engineering would be from lack of interest and attachment. That’s when we steered him towards schools that fulfilled the factors I cited above while answering @Rivet2000’s question.
I do believe this is the primary problem. It’s the main reason selective schools have higher graduation rates. A higher percentage of their students, for lack of a better term, are pre-screened for success.