Hi Guys... i have no idea about get valuable link though education and government sites like .gov and .edu
If you think backlinking to .gov websites will give you good backlink credit, them I am afraid you have to look for another alternate. Most of the .edu and .gov websites (if these websites are authority websites) have nofollow links. Second thing, every backlink carries equal weightage whether they are .gov backlink or twitter backlink. But if you are really intent on it, you may use a tool called 'Keyword Country' for finding .edu and .gov backlinks.