If she really wants to take the class because she'd like a personal deeper knowledge then go for it, but I honestly do not think it is necessary for the sole purpose of passing the interview. All she needs to know for that is the answer to the questions she can find in the flashcards, all the truly needed material for civics and citizenship study is provided by the USCIS website
here . Also she will get a free booklet/CD to study when she goes for her biometrics.
As far as the redesigned test is concerned...if she plans on applying in july 2008 she can still take the current test if she wants to, btw this is how it is going to work:
QUOTE
If an applicant:
Applies BEFORE October 1, 2008 and is scheduled for his or her naturalization interview BEFORE October 1, 2008, he or she will take the current test.
Applies BEFORE October 1, 2008 and is scheduled for his or her naturalization interview AFTER October 1, 2008, he or she can choose to take the current test or the redesigned version.
Applies AFTER October 1, 2008, he or she will take the redesigned version.
Is scheduled for his or her naturalization interview AFTER October 1, 2009, regardless of when he or she applied, he or she will take the redesigned version.
USCIS sourceRegardless of whether she wants to go to the class or not, I personally would wait a bit...I would forget everything by the time they gave me an interview, but that would be me.
ETA: when the time comes to file, do not forget to take a look at the
Naturalization Guide which has all you need to know about how to prepare your application.