I was perusing FB marketplace and spotted a lot of aboveground pools being given away.
It occured to me the frames would be very strong.
I search to see of anyone used the curved sections as arches for greenhouse.
I found that, but also people using them as the walls for a yurt style green house
Of the two, yurt style appeals more to me.
The poles needed can be very easy to come by.
You could use a central pole, or a reciprocal style roof.
You might even use a center pole and tensioned cables, circus tent style.
You could build a dome roof instead of a cone, there are many possibilities.
The opaque plastic walls should probably be replaced with translucent plastic on the southern side, and insulated on the northern side, but being largely weatherproof is a great starting point.
The floor of the pool could be used to cover the northern side of the roof, or left in place.
The hoophouse style seems to need more additional materials that would be harder to come by, but would look more normal , and where I grow, that would matter.