There are two basic ways education can be deductible -- through one of the education deductions/credits (Hope, Lifetime Learning, etc.) or as a business expense. I don't think that the education deductions/credits would work for flight instruction because those deductions I believe require that you be pursuing a degree or that the classes be taken at an accredited program. To be sure whether or not they could apply, review the IRS publication on eductional deductions as compared to your situation.
The more likely avenue is the business deduction. You generally can deduct, as a business expense, training expenses required to maintain or improve your skills in your current career. You may not deduct expenses incurred in pursuit of a new career.
Examples:
1. You are a current, working CFI, and you decide to add additional CFI ratings to improve your marketability. You may be able to deduct training expenses incurred in getting your CFI-I or CFI-ME because you would be improving/expanding your skills in your current career (being a CFI).
2. You are a C-ASEL, working as a pilot flying sightseers around the grand canyon. You decide that you want to get your CFI-initial and become a CFI in order to build even more time. You could not deduct the expenses incurred in getting your CFI-initial because the IRS has taken the view that being a pilot and being a CFI are two different careers. So the training for your initial CFI would be for a new career, not to improve your existing career.
Disclaimer: you get what you paid for; your mileage may vary; check with a tax professional of your choosing before you sign the line on your tax form that talks about perjury and prison.
MF