HI I'm just starting to write some lessons on approaching walking bass for beginners and post them on my website. I have a student that's a jazz beginner.
http://sites.google.com/site/bristolbassandguitar/
Go to the lesson pdfs page and it's at the bottom. I'm revising this over the next week. It's a starting out lesson familiarising the student with the basic changes of Summertime in Cm. Next will be Autumn Leaves, then a discussion of the 2-5-1 cadence using Summertime as an example of minor 2-5-1 and Autumn Leaves as an example of a major 2-5-1.
The exercises are formulaic but designed as a basis, rather than a piece to learn, so that it's not confused as a substitute for improvisation.