The distinctions between Bible Study/Study Guide/Workbook doesn't work at all for me - I need to know the author and publisher to guess which category something will fall under. Series are spread across the types.
I would strongly suggest that you reconsider these looking at the content rather than the whim of publishers. My suggestion (there are other reasonable proposals):
- Bible Study used for resources that are organized by scripture passages
- Study Guide used for resources that are organized by scripture topic
- Workbook used for resources that are on resources other than scripture.