We need to start with valid HTML A valid doctype and character set declaration are required. And in HTML 4.01 there is no "language" attribute for the SCRIPT element. And while you can do this without a FORM element it's a good bit easier with one.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta name="Content-Script-Type" content="text/javascript">
<title>Example</title>
<style type="text/css">
<!--
label {display:block; margin:1em 0em}
input {display:block}
-->
</style>
<script type="text/javascript">
<!--
function total (form) {
alert (form.elements[0].type)
}
// -->
</script>
<form action="">
<div>
<label><input type="checkbox">Accounting for Dummies - 39.95</label>
<label><input type="checkbox">Intro to Accounting - 48.36</label>
<label><input type="checkbox">Advance Placement Accounting - 27.95</label>
<button onclick="total(this.form)">Total</button>
</div>
</form>
Some hints...
1) You can either give each check box a name and then look up the price in your JavaScript or you can just assign the price to the checkbox's value attribute.
2) You will note that I've passed to the function the form object. This will greatly shorten your typing. From inside that called function you can get at the 1st element with "form.elements[0]".
3) From inside that function "form.elements[0].type" will equal "checkbox" if the first element is a checkbox.
4) From inside that function "form.elements[0].checked" will return true if the first element is checked.
5) From inside that function "form.elements[0].value" will return the value of the first element. However, it will return it as a string. Adding strings will cancatenate. To get at the number use Number(form.elements[0].value).