To gauge the long-term retention of information by primary and secondary school students, a random sampling of graduates should be tested, 2, 5 and/or 10 years after their graduation. They may be compensated for their time and effort by the government or school district. Such testing would help refine the development of a curriculum by finding out what pieces of knowledge are retained by former students and for how long. This may also encourage curriculum designers more focused on core materials and explaining them well, while minimizing tangential or peripheral information.