The dimensions are 38 inches wide by 80 inches long for the extra long. Standard twin is only 5 inches shorter. Almost any pattern could be lengthened by a single row to accommodate this, or you could add a wider border at one end and perhaps embellish it with something like an applique of the school mascot or "Class of 2024" or whatever seems to fit with the quilt. Unless your son is quite tall, the original length of the pattern will not cause him a lot of grief. Assuming he makes the bed at all, if it's a little short under the pillow, who will care?