The four-part practice test that includes science, math, social studies and language arts normally costs $24, and the GED itself costs $150.

Apollo also offers free classes to help adults improve their reading, writing, math and computer skills and a free class to prepare adults to take the GED.

Test-takers have the option to complete the online exam at home or in person at an official testing center.

Lydia Gonzalez, 46, uses the computer to study geometry for the GED math test at the computer lab of the Metropolitan Adult Education Program (MetroED) in San Jose, Calif. on Tuesday, July 2, 2013 ...