I purchased these from a seller who extracted them from a portfolio, so know they were made sometime between 1972-74 by a student with the last name of Laisney, surely for a fashion design class relating to pattern making / tailoring. I love them graphically, with these yellow construction paper forms cut and pasted against blue then detailed in red and/or black ink.  Rub off letters/numbers were also used for labeling, in French, with a bit of loss here and there to those. Easily trimmed down for framing, and quite striking I think.

The paper size for the top two in first photo measure is 17 3/8" x 12 3/8". The third (bottom one) is 12 5/8" x 10 1/4".  Pretty fun collage on the back of one of the larger ones too! Good condition, with a bit of loss to the labeling as noted and pictured. Blue is a bit lighter than photos convey. **First photo is a composite so relative scale is not exactly accurate.