var fDesc=new Array(); fDesc[0] = "Build an atom out of protons, neutrons, and electrons, and see how the element, charge, and mass change. Then play a game to test your ideas!Use the number of protons, neutrons, and electrons to draw a model of the atom, identify the element, and determine the mass and charge."; function tShowHide(id, show) { var s = document.getElementById("desc"); if ((s.innerHTML.length<=212 || show==1) && show!=2) { s.innerHTML = fDesc[id]; if (document.getElementById('m1')) document.getElementById('m1').style.display='none'; if (document.getElementById('m2')) document.getElementById('m2').style.display='none'; if (document.getElementById('more_txt')) document.getElementById('more_txt').style.display='inline'; } else { s.innerHTML = ''; } }