Early Sumerian education aimed to train scribes, bookkeepers, teachers and learners. There were organized classes and higher education available only to those who could afford it. Education focused on writing, mathematics, languages and vocations. Students learned through imitation, copying and preparing clay tablets. Subjects included reading, writing, arithmetic, astronomy, medicine and vocational skills. Education was financed through school fees, limiting access. Schools included home, temples and apprenticeship programs. A key contribution was the development of the cuneiform writing system.