OK i had some old plywood some 1/4 to 3/4 inch thick. i thought up this
with some 1/4 or maybe 1/2inch osb/plywood and 2x4s

take some 2x4 sink them in the ground and nail the osb to the 2x4.
There your talking 4 2x4s three piece of osb for three side $6 right now a sheet for the osb 2.22 for each 2x4. so for 30 bucks you got a 8x8 ground blind.

you could use longer 2x4 say 8 foot or 6 and nail a piece of osb or two on top for a roof
if you did the roof your talk 4 more 2x4 two to run down each side and two for cross braces in the middle and two more sheet of osb. so another 20 bucks

what do you think part of me thinks if you went with the roof you would need 4x4 in the ground not 2x4

i do not think it would make it more then one season.