It's annoying, I know.
By default Cake uses pluralization on table names and controllers, but not on models. See here for more info.
I made a decision early on to do away with this convention, and just go with the singular name everywhere.
I don't recommend doing this without doing a lot of research first, as it breaks the CakePHP convention and you then need to be aware of what's going on.
If you're sure that pluralization is more of a hindrance than a help, put this into your bootstrap.php file:
// Turn off pluralization altogether
Inflector::rules(
'plural',
array(
'rules' => array('/^([a-zA-Z_-]*)$/i' => '\1'),
'irregular' => array(),
'uninflected' => array()
)
);