In my Sharepoint project/Web Part/Web Page, I dynamically create page elements/controls using C# in the *.ascx.cs file.
In the *.ascx file, I use jQuery for responding t
You can hide an element like so:
$('...').hide();
Or you can slide it up with:
$('...').slideUp();
to get a nice sliding up animation.
On a side note, you can do this to multiple elements at once, in your case:
$('[id$=txtbxthis], [id$=txtbxthat], [id$=txtbxtheother]').slideUp();