There are several websites with free sample written driver's license test questions, including DMV.ca.gov, DMV.org, Driving-Tests.org and DriversPrep.com. Many states also offer free practice written tests on their state's DMV website, such as DMV.ca.gov.
While some of these practice tests are shorter in length, the DriversPrep.com sample questions include over 500 questions and answers that cover all areas of the DMV test, such as rules of the road and road signs.
These free practice tests are all relatively similar, since they base their questions off of the DMV manual and what are commonly asked questions. Taking several practice written tests helps to prepare one for the types of questions encountered on the actual test.