I really like SparkNotes. Not usually enough to pass an exam by themselves but very helpful as a supplement. I especially like the fact that they have review tests.

I did a lot of studying for the Biology CLEP with SparkNotes and it was extremely helpful.

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DONE! History degree from TESC!

CLEPS:
College Math-69, Sociology-70, Humanities-72, Am. Lit-61, English Lit-69, S. Sciences & History-65, Eng. Comp/w essay-75, Microec.-64, Macroec.-73, Western Civ. I-71, Western Civ. II-71, American Gov't-71, US History I-75, US History II-65, A&I Lit-77, Prin. of Mgmt-76, Prin. of Mktng-76. Biology-69

DSST's:
Civil War & Reconst.-70, Modern Middle East-63, World Religions-76, Tech. Writing-67, Prin. of Supervision-67, HR Mgmt-69, Rise & Fall USSR-64, Vietnam War-60, Ethics-69. Intro to Bus-67, Org. Behavior-69, W. Europe-60