Freeform check box group from entries
This my solution, although it's not perfect. I set-up an entry loop within the form and included the following for a series of checkboxes:

{% if loop.index == "2" %}

&lt;label&gt;
    &lt;input type="checkbox"
        name="{{ course2.handle }}[]"
        value="{{ course2.value }}"
        {{ course2.checked ? "checked" : "" }}
    /&gt;
&lt;/label&gt;

&lt;input type="hidden" name="{{ courseName2.handle }}" value="{{ entry.title 
}} | {{ entry.courseDate|date('j.n.y') }}"  /&gt;

{% endif %}


So in the form submission the entry title in loop 2 is attached to the Course 2 checkbox. It would have been better if {loop.index} could be used within the handle name so the 'if' conditional is not needed. As pointed out above, the value of the checkbox can be set dynamically from the entry loop, but the result is not shown in the FreeForm control panel, just the email notification. Therefore is was necessary to include the hidden field to record the entry title. Hope that all makes sense.