A few months back, we took the kids to Abiqua Falls.  It's a relatively short and easy drive up into the hills above Scotts Mills, OR.  The hike in is easy but requires some minor scrambling so we were pretty dirty coming out of it.  But that doesn't bother the LeBirches :).  And this gem of a waterfall is worth it! 

Abiqua Falls

The kiddos checking out some of the stacked rocks

For more info on Abiqua Falls, including directions, click on this link