I've looked at LOGO
in the past, but I've never used it for anything. It does look to be a good first step.
That said, my first programming language was commodore 64 BASIC, and I think it was great for beginning programmers, aside from the prevalence of the much disparaged GOTO statement.
A slightly more modern basic that I liked, which still has a good following is QBASIC
. It is a bit better at relating well to the more modern programming languages. Small Basic
looks to be a good modern solution, to me.
A couple of links I had related to this, that you may want to read:http://tedfelix.com/cs4kids/http://www.tedfelix.com/qbasic/
Good luck! I think you have a good idea, there.