How to post unchecked checkboxes

HTML

<input type="checkbox" id="AgeVerification" value="yes"> Are you at least 21 years of age?</input>
<input type="submit" value="Submit" id="submit" onclick="save()" />

JavaScript

$(document).ready(function() 
{
  function save() 
  {
    if (document.getElementById('AgeVerification').checked == false) 
    {
      document.getElementById('AgeVerification').value = 'no';
      document.getElementById('AgeVerification').checked = true;     
    }
    document.write(
    '<p>'
    +document.getElementById('AgeVerification').value
    +'<br/>'
    +document.getElementById('AgeVerification').checked
    +'</p>');
  }
  document.getElementById("submit").onclick = save;
})