There are two basic economic theories of how a college education improves an individual's wage. These coincided with the nurture versus nature views of human behavior. The human capital theory is education as nurture. Nurture raises an individual productivity. The other theory is education as a signal about the individual's ability. In this alternative model the individual incurs a cost by getting education. (This cost is typically modelled as the foregone wages and hence is viewed as an implicit time cost.) For the signaling to be effective, this implicit cost must negatively correlate with ability. Then it is rational for high ability individuals to attend college and low ability individuals not to attend and consequently for employers to interpret attending college as a signal of ability and paying a higher wage as a consequence.
There are many variants of each theory, but I don't want to elaborate on them here. Instead I want to ask which of these theories do we inside higher ed subscribe to? Clearly, those who focus on finding good pedagogic approaches to the use of instructional technology are thinking about education as nurture and hence whether they explicitly recognize it or not at least in that respect they are in the human capital camp.
However, if one pushes on the human capital theory a little bit and asks how best to allocate over time a given investment in human capital, one comes to the conclusion that early intervention is best. James Heckman, the nobel prize winner from the University of Chicago has argued this, among others. College education, particuarly at large public university such as mine, seems to cut against the early intervention idea in that freshmen classes are often large lectures while senior classes are where the seminars are. Furthermore, the freshmen classes are more likely to be taught by graduate students, who, however bright and smart about their discipline, are less experienced as instructors, or by adjunct faculty who typically are not purusing a research career. We have had a highly publicized Freshmen Discovery program that had small classes taught by regular faculty. But that program was seen as a luxury and Discovery program offerings were one of the things to go when the first round of budget cuts hit.
Recently at a presentation by Paul Kelter a professor of Chemistry and director of the general chemistry program on campus he argued and I think fairly convincingly that he'd rather have instructors with experience teaching young people and expert in the issues of making adjustments from high school chemistry to the college offering than to have research faculty doing this task.
Undoubtedly these adjunct instructors get paid less than the research faculty, so in considering the issue of early intervention simply looking at dollar outlay is not sufficient. One must look at the appropriateness of the investment. There may be inexpensive interventions that have high learning value. My belief in using students as mentor/teachers is meant to be considered in this light. In other words, we must get away from thinking about every possible intervention as mean lots of cash, because that is a very scarce resource. The challenge is to produce inexpensive but successful early interventions.
Otherwise we run the risk that the human capital approach will be swamped by signaling theory and that college will become a more Darwinian experience for the students.