Study System in Ancient Times

In ancient times learning was verbal.The students stayed at the teachers house for 10-12 years and the teacher teached, what he preached best for his students.No exams were taken.The knowledge became more efficient when the Guru thought so.
When the studies of the student were complete he left the Guru and gave him Guru Dakshina 
as fees and a tribute,sometimes he also served him for few years.
After studies the student was able to earn his livelihood and his life in calm manner.The student was much more efficient than those of today.