I'm not organized. I've put more stuff on www.resourceroom.net/devmath because good grief, the folder is shorter :P
The CASAS organization is non-profit, in California, and has some tests for adults tied to the "college and career ready" standards. It's what our Highway Construction Careers Training Program is using now.
So! I went to some sample questions and, like the GED, reading comprehension is critical. I made a
POWERPOINT to explain this question:
The circlue above has a circumference of 72 feet. What is the length of arc GH?
LOL I can see I need to add those letters :P but it's getting close to 5:00 already.
I started w/ reminder of what circumference means, and what "arc" means. 
... the missing piece of info being that we *do* know the whole circle is 360 degrees and that the angles and circumferences have a proportional relationahip. We don't know the "other part" for the circumference, so we can't subtract to find the answer.
Several other things have landed on my plate so images will have to wait.
GIMP file: Circle with radia for degrees every 15 degrees; all in separate layers so you can pick what you want to use.
Here's the .png image 
;
3 minutes and ... NOT a very good video, but "short and done" is the priority :)
This is a challenge for folks in our Math LIteracy course. I'm in the *middle* of buildng basic math online work but the folks at DeltaMath put out a call for folks to make videos... and this is the topic that a person applying to do the stuff (for compensation ;)) was to cover, so -- I did.. However, if I make it, it's OER.
So! Here's the link to the exponential growth video. And here's the link to the powerpoint I made it from because maybe you want to do something *like* it. It's OER -- yours to use, share... do kindly say you got it from Sue JOnes at www.resourceroom.net .
Subtraction One okay, time to go home, they're turning out the lights at work... (yea, it's 4:52 but it's like that.) I will figureou t the link at home... it's not that good, but ... I need it done. Next one is already done.