We love Lake Wenatchee and it has become an annual trip with a couple other families that we camp with.  The sites are roomy and well taken care of.  The bathrooms are clean and accessible.  There are some great trails that you can walk to and more if you're up for a drive.

The lake is beautiful, though it gets really windy in the late afternoon, so you'll want to spend you time there earlier in the day.

The town of Plain is close by and has a really useful grocery store with great ice cream and a good selection of emergency supplies.  There is also a laundromat behind the grocery store, just in case!