Validated Controls in Create User Wizard

My problem is that when the user is creating their account with my website, I need them to agree to some terms and conditions.  So I made a checkbox saying so, and dropped it into my Create User Wizard.  This is in a second step that I created myself.  I inserted the code saying that it needs to be validated, but it always just goes through whether I check it or not.
 
I have about 5 text boxes that I need to ensure have been filled out, and so I inserted the code: 
 
 <asp:RequiredFieldValidator ID="CityRequired" runat="server" ControlToValidate="txtCity"
                                            ErrorMessage="E-mail required." ToolTip=City is required.." Va ...