"I want my taxes to..." is a generally a bad start, because the point of taxes is it doesn't matter what an individual taxpayers wants to happen to them. Most taxpayers want the taxes to not be spent the way they will be. That is why they are taxes. If people had an actual choice then in all likelihood they wouldn't pay them.
I want all my nation’s taxes to contribute to a more-educated populace and I’m willing to vote to effect this.
Which, by extension, means education absolutely positively must be a group effort, even if taxpayers can't understand the n-order effects of severing tax money from education. If society needs the military, then it definitely wants soldiers who understand figurative language so that those soldiers don't shoot themselves in the foot. Being able to communicate well, critically think, understand history - these all come from the humanities (although the learner must go beyond the entry level courses to benefit).
I live in a 3rd world country, and due to the limitation of our weak taxpayer base, we can afford to fund only limited number of seats, which are won by certain competitive exams, and anything beyond that is considered 'self-finance' (i.e. figure it out on your own). Your country will have to decide its own limits.