How about a T-shirt quilt? Maybe their mom could slip some T-shirts to you.

I made my 14 yr old grandson a University of Oklahoma quilt.

And what 15yr old doesn't dream of a car? Someone younger,that's a little bit harder. I like the suggestion of a star quilt. Won't be outgrown, fits any decor.

I have done some for Quilts for Kids with baseball theme, hockey theme, soccer, etc. Can't go wrong with sports. Teen boys love dogs too. Am getting ready to make a quilt for my 15 yo DGS in shades of grey to go in his grey room. I have posted pics of my quilts in the past; maybe you can find them.

My son is now 27 and still uses two quilts I made for him at that age.....one is a football fabric with pennants and footballs in his school colors, no piecing, just two widths of fabric backed in fleece and sewed just enough to connect the two fabrics to each other. The other is a great basketball print with lots of color and movement with batting and a backing, again no piecing....and enough quilting to hold it all together. Some of you may not call these quilts but I do! :)

I think log cabins always work well for boys, usually I think teen boys don't care much, just maybe some nice masculine colors.

My daughter made this for her boyfriend - very masculine

Love it!

Maybe start with finding out their favorite color?

ask what they like ....... should be easy after that .