CAHSEE stands for California High School Exit Examination, and every high school student in California is required to pass it in order to receive a diploma (with the exception of some disabled students). State officials ordered the development of the test due to rising concerns that a growing number of students were graduating from high school without having learned very much, and would not be able to function in the workforce, or at college.
Proper preparation is essential, as the CAHSEE exams are not easy to pass, and the consequences of failure are so devastating to a person's chances at a decent life. In fact, California bends over backwards to help students pass the tests. They are given early on in high school, and if a student fails any part of the the exam, he gets many more chances to pass it. Juniors get two additional chances, while seniors get three additional attempts. Any section of the CAHSEE the student passes never has to be retaken; a passing score is permanent.
There are excellent study aids available for students who are having trouble passing any or all parts of the CAHSEE. These can include flash cards, study guides, classes, one on one tutoring, and more. While none of them are one size fits all, and not all of them will be ideal for every student, there is bound to be at least one study aid available that can make a difference in a particular student's test scores. A parent of a struggling student will want to decide which option to choose based on their child's learning styles, self direction (or lack thereof), aptitudes, etc. Of course, it's always wise to take a teenager's opinion into consideration when making these sorts of decisions, but the parents must have the final say, as they know what's best for their child. Costs for these training aids vary considerably, but there are more than one that don't require much of an investment and can pay off handsomely if the student will use them diligently.
Hopefully no training aids will be necessary. In many cases kids don't need any further help to pass the the CAHSEE. This shouldn't be surprising, as public schools in the state devote much of the time a student spends at school during the high school years specifically toward preparing them for the exam. This kind of intensive focus is what many students need in order to pass. For those that still struggle, the prospect of spending so many years in school only to leave without a diploma compels them to buckle down and get serious about passing the test.