yes,whipped cream is a colloid because the substances neve dissolve into each other like a solution and the substances never settle out eventually and mix together.such other exmples would be milk and gelatin. are you wondering fr a science project?=]
Cream doesn't change phase when being whipped, it just mixes with air. So whipped cream is a combination of liquid and gas - a foam. see also: http://en.wikipedia.org/wiki/Colloid