title: WPF, xaml Cad or drawing app examples?
body: <p>I am trying to learn WPF and xaml and am writing a cad style geometry app for my kids.  Does anyone know of an existing example written in VB.net?  C# is fine as well.  Thanks!</p>
  
  <p>EDIT:</p>
  
  <p>Any thoughts/examples on how to structure such an app?  TIA</p>