To remove the chapter starter and solution STPs from the site template gallery, perform the following steps:
OPEN the top-level SharePoint site where you previously uploaded the STP files. If prompted, type your user name and password, and click OK.
BE SURE TO verify that you have sufficient rights to delete STPs from the site template gallery of a site collection. If in doubt, see the Appendix.
On the Site Actions menu, click Site Settings to display the Site Settings page.
In the Galleries section, click Site templates to display the site template gallery page.
Click the Edit icon to display the details for the site template that you wish to remove.
In the toolbar, click the Delete Item option to remove ...