|Keep It Simple, Stupid|
LOGO is a bit of a special case. The language was specifically designed for teaching young children how to program computers. In fact, I suggest that the OP consider teaching his child some LOGO before moving to Perl. It has several traits that make it an almost ideal learning language:
-- The immediate visual feedback provided by the turtle's movements make LOGO programs more concrete than most programming languages. A diagram on a screen is much more staisfying (to me, anyway) than a line or two of text. Even if the text says "Hello, World!"
-- It has a Lisp-like "functional" structure which makes building a program out of re-usable pieces easy and natural.
-- It makes math, particularly geometry, relevent and therefore interesting. Indeed, teaching mathematical concepts through programmuing was one of the design goals.
I had instruction in LOGO for a few hours a week from 4th through 6th grade. I loved it, and I think it's a much more worthwhile use of computer time in school than word processing or (God forbid) typing lessons. There are free LOGO interpreters for just about every PC operating system in existence, and there are several excellent books for teachers. Unfortunately, very few elementry teachers seem to have heard of it, and even fewer feel competent to teach it.* LOGO deserves to be far better known than it now is.
-- Fuzzy Frog