What makes the GED difficult to study for is the breadth of subject material. To pass it is to show that you have learned enough of the material taught in high school to go on to college, and a lot is covered in five subjects through four years of a high school education. The subjects that are tested on the GED are writing, social studies, science, reading and mathematics. Like the SAT, the range of scores for each test is 200 to 800. To pass the test and receive a diploma, a student needs to score an average of 450 on the tests.
Over the course of history of the GED, the demographics of the people taking it have shifted such that today the majority are doing so in hopes of moving on to some form of postsecondary education. As this shift became apparent, the Adult Education and Family Literacy Act was passed designating money for adult education programs meant to help people complete their secondary education. These classes are offered for free or at minimal cost all over the country and provide the general skills and knowledge necessary to pass the GED. Check with your local community colleges or high schools for places where you can enroll in an adult education program.
Though the adult education courses are highly recommended for their value and organizational support, it is possible to study for the GED on your own. The important skills to develop for the GED are in the areas of reading and critical thinking. Because the GED covers things learned throughout high school, it is difficult to know what specific content will be tested for each of the subjects. However, practicing by reading high-school-level books and articles and then asking yourself questions about them is a good way to develop the needed skills.
Avail yourself of the many free practice tests and materials available online for studying for the GED. Each test may not cover the exact type of material included on the actual tests, but the structure of each test will be the same, and you can get a sense of the skills required to pass by reviewing the practice tests. While you can't know specifically what will be tested for each subject, there are basic skills required: correcting grammar in sentences, forming an organized argument in writing, identifying key points in reading and historical passages, reading basic charts and graphs, and having an understanding of basic algebraic and geometric principles.