// First you need to know that when following the DOM
// checkbox is a type of INPUT tag (tagName)

function countfields(){
	var table = document.getElementById("total-toys");
	var obj = table.getElementsByTagName('input');
	for (i=0; i<obj.length; i++) {
		var o = obj[i];
	 	o.onchange = function(){
			totalFields();
		}
	}
}
function totalFields(){
	var Total = 0;
	var table = document.getElementById("total-toys");
	var obj = table.getElementsByTagName('input');
	var totalbox = document.getElementById("total_toys_requested");
	
	for (i=0; i<obj.length; i++) {
		Total = (Total * 1) + (obj[i].value * 1);
	}
	totalbox.value = Total;
}
window.onload = function(){
 	countfields();
}