Solving word problems with reasoned judgement*.

What assures that a mathematical representation of a word problem is correct? The response of problem solvers to a request like "Explain your answer" does not necessarily provide assurance. Instead, we complement the traditional algebraic word problem with a request to establish a mathematical representation generalizing the problem situation and then to justify the derivation of this mathematical representation. Next, we suggest to construct a valid deductive argument and evaluate the justification. We give three examples of executing the suggestion. This contribution will increase the resources available to school teachers wishing to engage students in reasoning-and-proving activity. [ABSTRACT FROM AUTHOR]