Only the top 10 percent of workers on the PayScale.com list holding only a high school diploma or GED will earn over $100,000, Bardaro says. And workers with a high school diploma tend to earn more than those with only a GED, when other factors are held constant.

Continuing education courses, as well as years of experience, also may be required for licenses or certifications to garner the highest salaries in many these fields. But those requirements can often be attained at a vocational school or community college at far less of a cost than attending a four-year college or university.

Recent high school graduates certainly won't go from turning their tassels in June to making $141,000 a year switching on and off equipment at a nuclear power plant in September. For nuclear power reactor operators, "from a strict perspective, you can do this job with a high school diploma, but it does require a lot of specialized training," says Scott Burrell, a spokesperson for the Nuclear Regulatory Commission, which administers the examinations required for operators' licensing.

ScienceBuddies.org, a non-profit website that encourages students and parents to learn more about careers in the sciences, makes sure young people know how long it can take to reach that goal. Before even beginning training, a nuclear power plant worker must have 3 years of power plant experience. At least 6 months of this must be on-site at the nuclear power plant where the operator is to be licensed and traininggenerally takes at least one year before the worker takes the NRC-administered exam.

Training standards and requirements for massage therapists vary greatly by state and locality. Education programs for this job, at a private or public postsecondary institution, can require 500 hours or more of study to complete, according to the Bureau of Labor Statistics, and a high school diploma or equivalent degree is usually required for admission.

A certified executive pastry chefmust complete 150 hours of continuing education courses, as well as courses in nutrition, food safety and sanitation and pass a written and practical exam, according to the American Culinary Federation. Plus, to be certified, they must have worked for 3 years as a pastry chef in charge of food production in a food service operation and have supervised at least three full-time works in food preparation.

So getting a $100,000 job with no degree may not be as easy as pie, but for budding bakers, young scientists, and many other high school graduates the potential to earn six-figure salaries after some training may be much more satisfying than icing on the cake.

- By Sharon Epperson, CNBC Personal Finance Correspondent. You can follow her on Twitter @sharon_epperson