How about doing half square triangles in the 2 colours and forming the 4 squares into the pinwheel design? You could alternate blocks of zebra print background with teal pinwheels and teal backgrounds with zebra print pinwheels. I don't know if she will be helping to make it but if you do the half square triangles that you make by stacking 2 squares and sewing the seam allowance twice across the bias ( then cut apart) a 10 year old could be successful.