Hi,
Unfortunately, your Manhattan GMAT course cannot be considered as a tax deduction.
Recently, though, there was a case that a nurse won against the IRS for deducting the cost of her MBA. Maybe that would be a possibility for you?
http://bucks.blogs.nytimes.com/2010/01/ ... -your-mba/Best of luck!
Caitlin Clay
Student Services Associate
Manhattan GMAT