Here is a sample of my code. The checkbox ('p_drop_class') is the last item in the table. This example only has 1 row, but a real table would have more rows.
<form name="maint_student_schedule" action="stars3.star_portal.process_student_schedule" method="post">
<table width="100%" border="0" cellspacing=0 cellpadding=2 id="student_schedule">
<thead>
<tr>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Period</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Sem</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Class-Sec</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Name</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Room</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Days</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Teacher</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Status</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Drop</font></th>
</tr>
</thead
<TBODY>
<input type="hidden" name="p_start_yy" value=03>
<input type="hidden" name="p_school" value=KAF>
<input type="hidden" name="p_student_id" value=A013>
<tr>
<td>01  (07:00-08:44)</td>
<td>FY</td>
<td>112-001</td>
<td>ENGLISH 10</td>
<td>100</td>
<td>MTWRF</td>
<td><a HREF="mailto:001@SOMEWHERE.COM">FRANK, COSTNER</a></td>
<td><a HREF="STARS3.STUDENT_CLASS_ATT_DET.show?p_arg_names=_show_header&p_arg_values=YES&p_arg_names=_max_rows&p_arg_values=20&p_arg_names=_portal_max_rows&p_arg_values=20&p_arg_names=start_yy&p_arg_values=03&p_arg_names=school&p_arg_values=KAF&p_arg_names=student_id&p_arg_values=A013&p_arg_names=class_cd&p_arg_values=112&p_arg_names=section&p_arg_values=001&p_arg_names=period&p_arg_values=01" TARGET="student_class_att_det_window">Present</a></td>
<input type="hidden" name="p_class_cd" value=112>
<input type="hidden" name="p_section" value=001>
<td><input type="checkbox" name="p_drop_class"></td>
<tr>
</tbody>
</form>
</table>
<form name="maint_student_schedule" action="stars3.star_portal.process_student_schedule" method="post">
<table width="100%" border="0" cellspacing=0 cellpadding=2 id="student_schedule">
<thead>
<tr>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Period</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Sem</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Class-Sec</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Name</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Room</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Days</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Teacher</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Status</font></th>
<th BGCOLOR="#000063" nowrap align="left"><font CLASS="PortletText1" COLOR="WHITE">Drop</font></th>
</tr>
</thead
<TBODY>
<input type="hidden" name="p_start_yy" value=03>
<input type="hidden" name="p_school" value=KAF>
<input type="hidden" name="p_student_id" value=A013>
<tr>
<td>01  (07:00-08:44)</td>
<td>FY</td>
<td>112-001</td>
<td>ENGLISH 10</td>
<td>100</td>
<td>MTWRF</td>
<td><a HREF="mailto:001@SOMEWHERE.COM">FRANK, COSTNER</a></td>
<td><a HREF="STARS3.STUDENT_CLASS_ATT_DET.show?p_arg_names=_show_header&p_arg_values=YES&p_arg_names=_max_rows&p_arg_values=20&p_arg_names=_portal_max_rows&p_arg_values=20&p_arg_names=start_yy&p_arg_values=03&p_arg_names=school&p_arg_values=KAF&p_arg_names=student_id&p_arg_values=A013&p_arg_names=class_cd&p_arg_values=112&p_arg_names=section&p_arg_values=001&p_arg_names=period&p_arg_values=01" TARGET="student_class_att_det_window">Present</a></td>
<input type="hidden" name="p_class_cd" value=112>
<input type="hidden" name="p_section" value=001>
<td><input type="checkbox" name="p_drop_class"></td>
<tr>
</tbody>
</form>
</table>