I think if you say break down the figures from the attached people will probably figure out what you mean, but you could probably adjust the wording a bit to be more clear.
My concerns would be that
- The meaning of "break down" that's closest to what you're getting at really means that you're going to more or less destroy the thing, which is probably not what you want.
- Presumably "the attached" refers to the pages the figures are on, but all the pages are attached to the book. So that's kinda confusing.
I would substitute some more specific wording depending on exactly what is correct for this particular book.
If you're supposed to use scissors to cut the figures out, you could say
Cut out the figures from the appendix.
If the outline of the figures is already punched into the paper by a machine so you could just use your hands to punch them out of the page, you could say something like
Pull the figures out of the appendix.
Punch the figures out of the appendix.
However, if the figures actually are attached to the page, and not part of the page, then you could say
Pull the figures off the appendix.
Break the figures off the appendix
(Note that it's "break off" instead of "break down" in this case.)
Just go with whatever is accurate for the book.
Final note: Maybe go with "activity page" instead of "appendix," based off your other question?