Private markets will over-supply college classes. This is because there is a free benefit to society. Positive Externality Energy Education Higher education only gets more expensive. . Because there are positive externalities from higher education Select one. While not always easy to measure according to Walter McMahon the positive externalities to education typically include better health outcomes for the population lower levels of crime a cleaner environment and a more stable democratic government. What many of these individuals likely mean when they call higher education a public good is that higher education has positive externalities. Positive externality can be defined as this occurs when the consumption or production of a good causes a benefit to a third party an example can be education when people go in college. The club example from above is that of a negative externality. But also the rest of society benefits fr...