I am not sure what you mean by saying you paid for the subscriptions “for” your charity.  Are the subscriptions in the name of the charity, controlled by the charity, and available to the board and staff at all times?  And not available to you except on the terms available to all directors?  If so, you can probably claim a charitable contribution deduction for a gift of payment on behalf of the charity. Remember that if the cost of these subscriptions is $250 or more, you will need an acknowledgment letter from the charity saying you received no goods or services in return.

If, however, the subscriptions are in your name and you paid for them so that you could read them to improve your ability to serve on the board, I doubt that you will be able to deduct the costs.  You can claim a deduction for unreimbursed expenses that are actually required for your service, such as travel expenses to board meetings or the cost of special uniforms you have to wear while volunteering to provide services. But you can’t claim for costs that are deemed personal. You can get a feel for the IRS position on these issues from its discussion of contributions that are not deductible in Publication 526 on Charitable Contributions.

I doubt that these subscriptions are required for your service and expect that your “quid pro quo” equals the value of subscriptions. I suspect that the costs are not deductible.