Question: Eric, a professor and musician in Decorah, Iowa, wonders about the choice he made with his 529 college savings plan. He has two children, a 5 year old son and a 2 year old daughter. The Iowa 529 offers Vanguard funds with four aged-based options. He opted for one of the more conservative age-based choices. But he’s concerned that it’s still too aggressive, relying on stocks to do well. .

Weston: When kids go to college you need the money to be there when you need the money. I am concerned that the age-weighted option is too aggressive too late in the game.

What I plan on doing with my daughter’s 529–and this is just me–is when she’s a freshman in high school I’m going to put her first year college tuition into a money market fund. When she’s a sophomore, I’ll do the same with her second year’s tuition. And so on. I want that money in cash so that it’s safe and available when we need it.

Many people are comfortable with more risk than that. But we saw with the stock market crash a lot of people got shellacked with their 529s just when they needed the money.

I would err on the side of being more conservative. If you need the money within 5 years, have it in cash.

(Edited. You can listen to the conversation between Liz, Tess and Eric here. Liz Pulliam Weston takes on a couple of other listener questions, too.)