configuring checkbox fields on server side form posts

Anyone have experience with checkbox fields on server side form posts? I have most of our forms are server-side form posts and I've never had any issues configuring them but now we are trying to use checkbox fields too and having a bit of an issue with getting them to match up.

My code looks like this for example:

<div class="row">
<div class="col-md-3">
<input type="checkbox" name="Gooru_Admin_WP__c" value="Gooru_Admin_WP__c" id="admin"><img width="199" height="112" src="http://ift.tt/1PmHqtM">
</div>

Every other field is matching up okay, but the checkbox fields are just not yielding any results. Does anyone have experience with this? What am I setting up wrong?

I asked Marketo Support but they told me that server-side form posts are "outside the scope"