No, not on the fort yet. I need to be in a frame of mind wherein I'm willing to dig four post holes pretty much by myself and square up the posts. Probably next week.
JT recently joined Webelos, the thing between Cub Scouts and Boy Scouts. It is my great hope that his dad-the-Eagle-Scout will do the boring memorization things with him and I can do the cool stuff.
To wit!
One of the projects was to build a catapult. There were even instructions in the new nifty Webelos book we got. Of course, I'm allergic to instructions, so we used a shoebox instead of a milk carton and chopsticks instead of pencils. But it works!

He wanted to build a birdhouse next. Bor-ring! One of the recommended projects was a really simple shelf. I decided to up the ante and build a baseball equipment rack. He heard my description and ran for his safety goggles.
This is good practice for the fort. He got to use the jigsaw for the first time and both drills (because I'm also allergic to keeping the cordless drill's batteries charged). He liked the drill, except when we had to use the doorknob bit. He was less impressed with the loud jigsaw. We eventually put him in his batting helmet and that helped minimize the noise.
He also learned such basics as unplug the drill before you change the bit, look what you're braced against so you don't saw through something you don't want cut, and--for pity's sake!--
stop stepping on the equipment! Oh, and everybody hates sanding.
I didn't take any pictures as I was too involved trying to prevent the sudden loss of fingertips. We cut out all but the sides of the rack, and I'll take some pics as we put it together. Please don't expect to be impressed. I am not a carpenter. I can't even guarantee it'll stay together.