"Who wants to look at another galaxy?!" Way more interesting than those hum-drum nearby planets you hear about all the time.
"How far away is it?" they'll ask.
"2.5 million lightyears," I'll say. "Light travels really fast, right? You see it as soon as you turn it on, even from far away. But even light has a speed limit. And as fast as it moves, the next-nearest galaxy to us is so far away that it takes 2.5 million years for that light to reach us."
The middle-school aged kids can think about it for a second, and then they realize, "So that light we're seeing started 2.5 million years ago?" and they are awe-struck.
"Yes," I'll say. "And that's the closest galaxy to us!"
I also like to talk about how our galaxy and Andromeda will collide - sans any actual collisions, because space is big and things are far apart. Except for the fact that the black holes will probably merge. Then I'll show them one of my pictures of M31 so they can see what it really looks like.
After M31, I slewed to Uranus, since it was very near opposition, and thus large and bright. Well, as large as Uranus gets.
"Who wants to come see Uranus?"
Not that pronouncing it "UR-a-nus" is much better than "ur-ANE-us." I'd be game for "ur-ANN-us," but it'll never catch on.
Uranus did look wonderful in my 8-inch - it was obvious that it was not a star, since you could resolve the disc shape, and easily see its blue-green color.
I tried for Neptune next after a while, since it is also not too far from opposition, but the goto on that mount is not spectacular (even with Precise Goto), and I couldn't tell which of the several dots in the field-of-view it might be.
After the crowd died down, I decided to try and image it. I knew my blue filter wasn't doing well, but I thought I'd try anyway. But since it's quite dim, I had to take rather long frames, 10-30 seconds depending on the filter, but the mount wasn't doing well enough for it to stay put for that long, so I gave up. One of the other club members let me try on his scope, but I was having trouble getting it centered in the field-of-view. It was getting late, so I decided to scrap the idea. Maybe another time, and I'll try the Orion StarShoot Color Imager IV I won at Hidden Hollow last year. It's not as sensitive as the QHY5, and I have trouble making it talk to one of my CCD capture programs, but we'll see. I can't use my DSLR because those longer frames mean I can't use video mode, and the shutter will cause too much vibration if I use eyepiece projection to get some magnification on it.
All in all, a fun evening! I probably had about 50 parents and kids come look in the eyepiece. I always love doing outreach events!