Idaho written test: 34 of 40, $5 a try, 3 day wait

The Idaho Driver's Manual gives the Class D knowledge test as 40 questions with 34 correct required, which is 85 percent. Almost every state that publishes a mark at all uses 80 percent, so Idaho's exam allows six wrong answers where a proportionally scored 40 question paper elsewhere would allow eight. Questions are drawn directly from the handbook, which makes the manual the entire syllabus rather than background reading, and there is no separate road sign section that has to be cleared on its own inside that score. The practical effect of the higher bar is that a single weak topic can end an attempt, so working the manual chapter by chapter is a better use of time in Idaho than sampling questions at random.

Idaho bills the knowledge test on its own. The Class D knowledge test carries a $5 fee separate from the instruction permit charge and from the skills test charges, and every fee in the process is non refundable, so a failed attempt is money spent. A failure also carries a mandatory three day wait before retesting, and the $5 has to be paid again for the new attempt. Anyone under 17 who has never held an Idaho license reaches that exam only after an approved driver training course and the state's Graduated Driver's License program, whose supervised period runs a minimum of six violation free months with at least 50 hours of practice driving, ten of them after dark.