I have been working on mine slowly (the heat brought work to a standstill) but I am photographing as I get each section completed. Mine is a three-phase project. It was gonna be an 'article or idea', but you can have a sneak peak at 'Phase One' of the project.
The slope is not steep; only 12 inches in a 15 foot run. Here's a rough sketch (everything was approximate and some measurements were changed after the photo was taken). The box is 4 inches at the shallow end near the house and 15 inches at the street end.
The build was done up-side-down on a concrete pad so the top would be level, so the first picture here is actually the bottom side (don't think the worms will mind). Basic construction of the part of the box that is visible from the street side; transition from all wood to 1/2 wood - 1/2 plastic at the midpoint; you can see where I used the plastic 'wood' which will be hidden from view for the most part by Liriope (rhymes with Calliope). That's a 2-foot level and a half-size shovel in the photo for size reference.
Oh, gosh, how did that photo sneak in?
Jack is inspecting my work.
A 27 pound dog for size reference.
And finally the before/after pictures of phase one.
I did all this because I didn't get time to plant a Tung Oil tree and it grew roots through the pot.