A = Light (white)
B = Medium (Light Blue)
C = Dark (Dark Blue)
 

Cut 6 3.5" squares of color A (white)
Cut 6 3.5" squares of color B (light blue)
Cut 4 3.5" squares of color C (dark blue)

Cut these 3.5" squares on the diagonals to make triangles
Sew together 8 sets of triangles using colors A+B (White and Light Blue)
Sew together 4 sets of triangles using colors B+C (Light Blue and Dark Blue)
Sew together 4 sets of triangles using colors A+C (White and Dark Blue)

These should make 3" squares

Arrange squares in the pattern shown above and sew together the blocks to make the Grandpa's Favorites block.