I just got my first look at this for the first time yesterday while visiting with another homeschooling family.
The main book for each math level (they are starting with grade 3) is workbook size, but written like a graphic novel/comic book. Very fun, colorful, inviting. The related workbook then takes the learner through activities and exercises.
These are still really new, so limited availability. But they look like a lot of fun.
I'm considering getting the 4 book set soon...waiting to see if the price comes down when Amazon starts selling them directly instead of just via a seller.
(I'm not selling these nor have any connection to the publisher nor get any benefit for promoting them either from the publisher or from Amazon. I just wanted to share a fun, new math resource.)