So many masculine designs come to mind. It's all in the fabric that's selected. Some ideas:
A mix of different plaid fabrics cut into simple squares. (I LOVE this look and definitely prefer masculine to feminine designs.)
Hunter's Star, Carpenter's Star or similar pattern.
Brick or block pattern in any medium to dark colors/prints.
Pixel designs of whatever is currently hot with that age group. (Computer game characters?)
A simple jelly roll race.
Stack & flip.
Half square triangles arranged as pinwheels, chevron or other layouts.
Strip tubes give a lot of design options.
A simple background with one medium- to large-size applique of something sports related (baseketball, football, baseball and bat, hockey sticks, etc.).
A simple background with a few appliques of something outdoorsy/woodsy (howling wolf, fox (non-cutesy version), owl in a tree, fish swimming or jumping, deer (head with nice antlers or side view of whole deer), etc.).
Rail fence.
Just simple horizontal strips of various colors or prints. I really like the "Quick Strippie" from Mary's Quilts blog.
Even something like 9 or 16 patch in bright, happy colors sashed in black would be nice for a young man that likes colorful things.
Scrappy quilt of simple squares or rectangles.