function OpenLetters(){
   PopUpWindow = window.open('letters_sounds.html','textWindow','scrollbars=yes,resizable=yes,width=512,height=375,alwaysRaised');
   PopUpWindow.focus();
}//end OpenLetters

function OpenBooks(){
   PopUpWindow = window.open('reading_books.html','textWindow','scrollbars=yes,resizable=yes,width=512,height=550,alwaysRaised');
   PopUpWindow.focus();
}//end OpenLetters

function OpenBlending(){
   PopUpWindow = window.open('blending.html','textWindow','scrollbars=yes,resizable=yes,width=512,height=470,alwaysRaised');
   PopUpWindow.focus();
}//end OpenLetters