Where to put extra college savings beyond 529?

[kmm]

Hello, I have a reasonably good problem to have thanks to a generally mustachian lifestyle. My son is 6 years old. According to the college savings calculators, his 529 has enough in it to pay for a 4-year public university. I'd like to save more, in the event that he decides to go the private school route, or continues to graduate school. I am maxing out retirement funds which have a healthy balance, have a 2-year emergency fund, am pre-paying the mortgage, and am happy in my job, so the extra savings will not derail any other goals.

I know a lot of people think private colleges aren't worth the cost. I was fortunate enough to attend a good one debt-free, and I made the most of it and have done well professionally. I'd like to give my son the same option, or at least the option to do so with minimal debt.

My question is, where to put it? I prefer not to put any more into the 529, partly in case it's not needed, and partly because I can't tax-free until 2015 due to a lump-sum payment a few years ago. I was thinking about a Vanguard target retirement fund geared toward the year he starts college (about 2024). I also have a taxable brokerage account where I do my own post-retirement investing, so could just add it to that, although the nerd in me likes the idea of it being separate so I can track it better. Any advice? Any tax-advantaged options I am not thinking of? I make too much for a Roth or Coverdell.

Thanks in advance for your thoughts.

[chucklesmcgee]

Any tax-advantaged options I am not thinking of? I make too much for a Roth or Coverdell.

Thanks in advance for your thoughts.

Well there's the backdoor Roth IRA contribution for high earners. Otherwise I can't really think of anything tax-advantaged. Still, the tax exempt earnings of the 529 should be pretty substantial for your 6 year old son, right? And you should still be nowhere near the contribution limit, right?

Despite the enormous talk by politicians in enabling access to higher education, most of that has come in the form of offering students easy access to debt. The Feds don't have too much concern for people who are well enough off (or diligent enough) to save for even a semester or two of their children's education. The 529 is pretty much it in terms of tax-advantaged education accounts for the "rich".

[kmm]

Thanks for your replies! Backdoor Roth and I-bonds are both new concepts to me so I will do some due diligence and check them out. I feel like I'm a good saver, but a poor investor - I can be much too emotional and reactive. So I need something I don't have to manage very actively. Otherwise I can be my own worst enemy.