<p>Does the first semester of your senior year count when colleges are looking at your GPA?</p>
<p>Yes, unless you are admitted ED or EA. Still, you have to send them and if you slipped substantially, they could rethink admission.</p>
<p>Other than EA or ED, it actually depends on college. For regular admission, many (likely the majority and definitely most public universities) do not use first semester senior year grades for determining admission but only grades through junior year and thus GPA through junior year is what counts. On the other hand, a very large minority (including most of your high ranked private universities) require you to submit your first semester grades after you have applied and those are used to determine admission.</p>