ensure an intelligent, elected leadership that has some sense of what they are doing

Elected officials should understand the issues put before them and have knowledge of the core subjects on which these issues rest. An elected official should have a basic understanding of economics, geography, science, law, social issues, history, etc.
While there should be no formal educational requirement to hold office, our elected officials need to be able to comprehend complex and important issues and inform/represent the public intelligently.
I propose a standard knowledge proficiency be established for elected officials with a corresponding pass/fail test. Any official running for office in the Legislative or Executive branch of the US Government will be required to take this test (at their cost) and only those who satisfy this proficiency will be put on a ballot.