A great tool that Andrew Jones talked about in the En-Roads training is the Climate Bathtub which helps people to understand the concept of stocks and flows when thinking about CO2 emissions and atmospheric levels.
I have built on this Climate Bathtub Concept in one of my short videos which is part of my Climate Concepts resources which you can find on my website.
In addition I have prepared a set slides which link the concept in the video to the relevant graphs in En-roads. See link
I am currently piloting these tools in workshops with people who have a limited knowledge of climate change and science. You might find them useful too; if you do use them I would love to have your feedback!