help with if ($thispage ==

Im working on my footer navigation bar and while its not needed I thought it would be nice to highlight the active page on it.... I know theres a $thispage in php but I apparently dont know how to implement it...

anyone have an idea how to use this? this is what I tried:

<li class="fmenuvert"><a <?php if ($thisPage=="plans")
echo " class=\"currentpage\""; ?> href="/plans/">Our Plans</a></li>

then I would do a class in css but I obviously did somthing wrong lol...