A new school year will soon begin. And if you have young children, that means it’s one year closer to the day when they head off to college or some other post-secondary education or training. You might be preparing for that day with a 529 education savings plan — but should you be concerned if you need to start taking withdrawals to pay for education expenses when the financial markets are volatile?

Long-term investment vehicles based on the financial markets, like a 529 plan, will always flu...