Every so often I sit down and sketch up a design I think would be cool to build. I posted this previously with a rough idea I had if you redesigned an Australian Six Footer and made it into a very tiny singlehander.
Below is a sketch of a very simple junior boat based on a punt/barge type, the bottom being essentially three flats. You could build it out of 6mm plywood with some stringers, or some rough lumber, cross planked, as they did in days of olde. You could put all your framing/cleats on the outside of the side panels as Bolger did on some of his QD (quick and dirty) boats - or not.
I call this design "Kid Simple". I originally designed it to be a good rowing boat (there is supposed to be a thwart just aft of the daggerboard case to sit on for rowing) and then added a sailing rig based on the sprit rig of the Optimist. I started off large and then made it smaller (the original length being 10 1/2 feet and then shortened it to 9.9 feet length, by shortening the bow flat - I'll let the reader do the metric conversions). It has a healthy skeg to help in tracking when rowing and I would envision a large rudder close to the Opti in size.
Here are two JPEG's. Dimensions in feet, tenths of feet, or sometimes inches. Again you can use the pop-out icon in the top right of the drawings to open in an another tab to print.
The first sheet has the original idea with modifications noted.
The second sheet has a modified sheer and length and includes the rig.