One common practice of law school graduates is to take an intensive bar review course before taking a state bar exam. These courses are designed to provide participants with a review of key concepts, state laws, and legal history covered in the exam. Many individuals who complete apprenticeships and "read the law" find it helpful to take these courses prior to taking the bar exam. In addition, those apprentices who are working full-time may also find it helpful to take a few months off before the bar exam to study the material full-time.
In summary, it is possible to work as a lawyer without going to law school but there are no shortcuts to learning the law. On the upside, completing an apprenticeship and "reading for the law" may provide you with all of the experience you need to determine whether a legal career is right for you - without incurring a large debt in law school loans.