Secondary education usually refers to high school grade levels, while post-secondary education refers to the training received after that. Types of post-secondary education vary widely -- from university, college, trade schools and apprenticeships -- but what they all have in common is that they come after, not before, secondary education. Secondary education in the U.S. generally begins after grade eight and continues through grade 12.
Difference in Stages
The most obvious difference between secondary education and post-secondary education is that the commencement of one follows the completion of the other: post-secondary education comes after secondary education. Most post-secondary programs will not admit someone who does not hold a high school diploma. There are many exceptions to this, however, particularly among trade schools. But, as a general rule, you have to finish high school before moving on to post-secondary school.
Difference in Level of Difficulty
Because post-secondary education follows secondary education, a post-secondary program will often build on what was taught during a secondary education. For instance, a university math major will not have to relearn what she learned in Grade 10 math -- the curriculum will be more advanced and, therefore, more difficult. In the arts, you may review some of the same material you studied during high school, but expect a university treatment of "Romeo and Juliet" to be far more in-depth and analysis-driven than the high-school version.
Difference in Specialization
Even the most general of humanities degrees is more specialized than high school classes. High school students have some choice of what classes to take, but many are compulsory. In university, college, or trade school, you effectively pick your classes by picking your program. So if you never want to take chemistry again, no problem -- just be sure to avoid the hard sciences after high school. Over three or four years of college or university, you're expected to become an expert in your topic of study.
Difference in Cost
Secondary education is usually free for students, with the exception of private schools. Post-secondary education, however, is often more costly. Fortunately, the cost of post-secondary education programs can be alleviated through bursaries and scholarships. So while funding a post-secondary education is usually more difficult than funding a secondary education, don’t let that fact stop you from trying to further your education.