That depends on a few things that you haven't told us about the setup. So I'm going to assume one of them, and then give you the answer in terms of another one:
-- Assume a Class-I lever . . . the fulcrum is between the load and the effort.
-- Then the effort needed to lift the load is
(the weight of the load) x (13 / the distance between the fulcrum and the effort)
I think the students claim is wrong because according to Newton's First Law an object that is in motion stays in motion unless acted upon by an unbalanced force. Which makes the students claim wrong because a object doesn't require another force to keep it moving.
