I think kangaroo pockets are those that they put on the side of the pants legs now,ya know the square ones.They're mostly on guys pants,as ya know we gals don't like anything else added that will add to our size.LOL
HTH
Kathi

A kangaroo pocket is like a pouch on the front of a sweatshirt. A pocket sewn completely on the outside is a patch pocket. Ones in the side seam are set-in pockets. Patch pockets that have pleats for fullness and usually have some type of closure are cargo pockets.

Donna

Look in a good sewing text for pockets and how to sew them.