Here's a simple block to make with feed sacks and solid cottons. It finishes 8 in. square.
For each block:
Cut 4 2.5 in. squares of print feed sacks, 2 of each print, and make a four patch.
Cut 4 rectangles from the white feed sacks, each measuring 2.5 in. x 4.5 in.
Make 4 triangle-squares that finish 2 in., using your favorite method, from white feed sacking and a solid color that goes with the print feed sacks. I like to use the Easy Angle tool and cut the triangles from 2.5 in. strips. Then I sew them together in pairs.
Now the triangles are sewn into squares.