can you increase the size of the icons? more bigger for eg. or like custom sizes? what determine this the size? thanks

By icons, do you mean the favicon next to the title of page? If so then no, the browser determines the size. Any other type of image can any custom sized.

Icon fonts can be resized too, i suggest downloading the larger image and just resize it down. Although most icon fonts are not very large so it depends on what your looking for.

thanks for the quick answer, the aproach i want to do is like this theme, http://circleswp.wpengine.com/

in the place are 3 columns, "Deep Reseach" , "Unique Aproach", "Advanced Support", he is using a sprite , i am not sure how i can do the similar with zurb , i have a hover effect too, maybe using block grid? or icons? thanks for the help.

That looks like it could be done using the @font-face rule.

http://teamtreehouse.com/library/css-foundations/web-typography/web-fonts-2

thanks i will check

I know this post is quite old but I just want to mention that to change the size of the icons used by the icon-set available on the foundation website, you just need to use the classical css property which is font-size, quite normal as these icons are really fonts. As nobody mentionned it, I prefered to tell it here, as the question is related to the foundation course... Besides this detail, I've noticed as well that using i tags for applying our icons with the appropriated classe doesn't work correctly with foundation 5, it does with span however...

In fact these icons haven't been tested with the last version of foundation 5, there is a warning on their page..

Not Tested in 5

We made these add-ons to be pretty robust, but they have not been tested in Foundation 5 yet. Watch out for gremlins if you're using Icon Fonts, Responsive Tables or the SVG Social Icons with Foundation 5.