Mesh included, however I do recommend that you visit Cocomama's post
here as she has also made other wonderful mesh conversions for teen guys.
Here are 32 patterned shirt re-colours for Cocomama's open shirt with jeans for teen guys mesh.
They are organised into 8 sets with 4 outfits in each set.
Set 1.

Set 2.

Set 3.

Set 4.

Set 5.

Set 6.

Set 7.

Set 8.

Credits:
Mesh - Cocomama