How to Change Height of Rectangle on Keypress ?

I am trying to figure out how to change the height of a box when a user presses up on the remote. 

Heres the component:

<component name="PlutoScene" extends="Scene">

  <script type="text/brightscript" uri="pkg:/components/homescreen.brs" />

 <children>
 <LayoutGroup id="root">
      <Rectangle id="header" width="1280" height="300" color="0x000000"> 
      </Rectangle>
      <LayoutGroup id="body" layoutDirection="horiz">
        <Rectangle id="rect1" height="270" width="400" color="0xffffff" />
        <Rectangle id="rect2" height="270" width="2" color="0x000000" />
        <Rectangle id="rect3" height="270" width="878" color="0xffffff" />
      </LayoutGroup>
      <Rectangle id="footer" width="1280" height="150" color="0x000000">
      </Rectangle>
    </LayoutGroup>
 </children>
</component>

Here is the function in the homescreen.brs file:

sub init()
  m.rect1 = m.top.findNode("rect1")
  m.rect = m.rect1.boundingRect()
end sub

function onKeyEvent(key as String, press as Boolean) as Boolean
  if press then
    if (key = "Up") then
      m.rect.height = m.rect.height * 2
    end if
  end if
end function

I have tried a few things like just calling rect1.height = rect.height*2. 

Is the if statement correct? Am I grabbing the component correctly? What concept am I missing?