We keep most of our fave spots "secret" from others, as I've made the mistake of inviting some friends along to our family trip, swear them to secrecy (lol)  they end up loving it of course , tell some friends inevitably, and then it gets harder and harder every year to book!  We have a pop up camper, nothing uber fancy, but bring lots of toys (kayaks, paddleboards, bikes) and our kids love love it. Paved pathway for the kids to safely bike on while you're setting up or cleaning up.  

Be wary of camping in too early of June (can be snow and very windy), or late August (smoke can settle here from fire season nowadays), but July is usually the sweet spot.  It can get very windy on the water from midday-4pm most days, and as we learned one trip, don't attempt a paddleboard across the lake to the hotsprings..it's a BEE-yatch to make it back safely!  My arms and legs nearly fell off from THAT treacherous paddle.  We always bring tow lines for our younger kids when they tire out of paddling their kayaks too, and the best time on the water is morning until noon, then again between 4-6pm, when things usually calm down.  Motorboats are allowed (lots of fisherman hit this lake early morning), so the parking area in middle of campground can fill up, but the views, the sunsets, the easy access to some fantastic obsidian hikes up the Butte to the right of the lake, the steep climb /  big Paulina hike or bike ride (whew!) , and Paulina and East Lake lodge a hop skip jump away for when mama is tired of cooking ...this place cant be beat!  Bring sunscreen!  And a Shade Tent!  Many campsites are not very shaded, and don't let the 75 degree and a lovely breeze fool you.