I’ve been making folding camp furniture. The stools are sometime called “pea-pickers”. They were somewhat difficult to figure out without a plan but some photos of others and experience making other furniture helped.
They’re not as easy to make as I thought they would be. The holes must be very precise and dowels tight-fitting. If everything isn’t square and precisely cut, the stool just doesn’t work.
This is their beauty. They fold flat and have an integrated handle. They can be made just about any size and out of any straight lumber. My first one is made from scraps from around the workshop. These later ones are from premium pine.
Seventeen pieces, twelve holes. Stick ’em together. Sit. Mine are sturdy enough to use as a step stool, with some caution due to the narrow width.
A table of similar construction. The top is about 22 x 46″. I made it 2 inches lower than a standard table to fit the stool height. A combination of pine, poplar, and oak. Definitely strong enough if it is well-fitting.