//ad rotator
  function rotAd(){
  //rotating ads array
    var rotAds = {
       1:Array('http://www.thehomeschoolmom.com/cgi-bin/lnkinlte/to.cgi?l=mg468','http://www.thehomeschoolmom.com/images/ad/graph_homesch_v2.gif','Mrs. Glossers Math Goodies helps kids learn math!'),
	   2:Array('http://www.thehomeschoolmagazine.com/subscribe/promo_subscribe.php','http://www.thehomeschoolmom.com/images/tosbanner2.jpg','19 Free gifts from The Old Schoolhouse Magazine!')
    };
	

  //last ad
    var sAd = loadme('rotAd');
    if (sAd=="") sAd = 0;
    sAd++;	//perform rotation
    var aAd = rotAds[sAd];
    if (!aAd){
      sAd = 1;	//set to first ad
      aAd = rotAds[sAd];
    }
  //save state
    saveme('rotAd',sAd);
  //return
    document.writeln('<a href="'+aAd[0]+'"><img src="'+aAd[1]+'" alt="'+aAd[2]+'" border="0"></a><br />');
  }

//cookie handling
  function loadme (name) {
    var ne = name + "="; // name+equals
    var al = ne.length;  // name length
    var cl = document.cookie.length;
    var i  = 0;          // iterator
    while (i < cl) {
      var st = i + al;   // start at
      if (document.cookie.substring(i, st) == ne){
        var en = document.cookie.indexOf (";", st); // end
        if (en == -1)  en = document.cookie.length;
        return unescape(document.cookie.substring(st, en));
      }
      i = document.cookie.indexOf(" ", i) + 1; // next
      if (i == 0) break; // end of the line
    }
    return "";
  }
  function saveme (name, value) {
    var ckd = new Date();
    ckd.setDate(ckd.getYear()+1);
    var cv = name+"="+escape(value)+ ";"; // value
    cv += "expires=" + ckd.toGMTString(); // expires
    document.cookie = cv;                 // store it
    return(true);
  }