So, all sets are upgraded to include all 20 titles. The original 19 plus the latest title: Think About the Garden.
Just about $5.49 per title!
You'll receive all 20 Little Thinker titles on one USB/thumb drive.
If you have a modern car (not like mine!), you can just plug this drive into your car audio system, and play all 20 Little Thinkers directly, without CDs or MP3s on your smart phone.