Using A Two-Column Proof To Argue With Parents

I've always enjoyed books on logic. As opposed to pulling my hair out while studying it in college, I once attended an online seminar with David Gordon of the Mises Institute titled “How To Think: An Introduction To Logic”. I can't recall the text we used for the course but it was a fun class. Anyone suffering through an elementary geometry class has, at some point, witnessed a two column proof in which the left hand side is used to denote a proposition while the right hand is either an axiom or something that can be derived from a former proposition (sometimes a hypothesis as well). Like so,

The purpose of this exercise is nothing more than introducing the two-column proof by allowing students to create a method for arguing with their parents. My advice would be to hook the class by asking, "what is something your parents won't let you do? Has anyone tried arguing with their parents? I mean really arguing with them and showing the flaw in their statement? Let me teach you"

 NOTE: The outline below is nothing more than a fun, informal introduction. It's merely an attempt of playing with the process of creating a proof, the arguments presented below will be like that of a young child.


The argument presented is as follows. You want a cell phone but your parents claim you can't have one because you don't have enough money to pay the bill and you might run-up their bill (you could also use you are not old enough). How are you going to prove to them that this statement is not true. Or in essence, how can you prove that you do, in fact, have enough money for a cell phone.