Gordon Peters of the Association of Iroquois and Allied Indians is raising the possibility of a blockade on the Ambassador Bridge between Windsor, Ont., and Detroit if the bill is allowed to pass.
But Peters and other First Nations leaders also say they shouldn't have to make threats to have their voices heard.
They say the federal government did not consult widely enough when it was drafting the legislation, dubbed the First Nations Control of First Nations Education Act.
Aboriginal Affairs Minister Bernard Valcourt has said Bill C-33 meets the five conditions outlined by the Assembly of First Nations and chiefs during a meeting in December.
Those conditions called on the government to ensure aboriginal communities retain control of education, and to provide a statutory funding guarantee, recognition of First Nations languages and culture, shared oversight and ongoing, meaningful engagement.