A patent pending would be considered an activity and not an award. Alternatively, you can include it under the “Additional Information” section of your applications, where you will have more room to explain it … how you came up with your idea, how you implemented it, etc.
But rest assured that admission officials realize that it can sometimes be tricky to distinguish between an “Activity” and an “Award,” so students will not be penalized for entering some endeavor under the “wrong” heading.
Good luck with your patent … and with your college acceptances.