My very first tank kit, built when I was probably seven or eight years old in the early 1980s, is the small diorama at the left front — that is, the Matchbox 1:76 scale Panzer II. I painted it some years later, which is why you can see the outline of the decal on the ruin under the paint above the right-hand door.
The small one at the right front is a Revell reissue of that same kit, that I bought and built (but never quite finished) maybe fifteen years ago.
The large version is a scaled-up copy of these, using the equally ancient Tamiya Panzer II, a piece of plywood for the base and styrofoam for the building, both covered in wall filler. More photos here 