Too many books on investing and personal finance try to exploit the prevailing mood of the public, be it fear or greed.

In boom times, they tout fancy stock-trading strategies supposed to juice up returns. In tough times, they promise to "recession-proof" our portfolios.

Sadly, many of these "timely" books are rush jobs full of platitudes that serve mostly to promote the author's agenda (or product). Give me instead a "timeless" book with common-sense advice for good times and bad, even if I don't agree with everything it says.

The newest such book I've read, published in March, is "How A Second Grader Beats Wall Street: Golden Rules Any Investor Can Learn" (Wiley, $24.95), written by Allan Roth, founder of Wealth Logic, a financial planning and investment advisory firm in Colorado Springs.

The second grader - now in grade 5 - is the author's son, Kevin. Roth, a certified financial planner, taught Kevin basic concepts of investing when the boy was in second grade.

Roth imparts the same lessons in the book, making the point that adults tend to unnecessarily complicate things, including investing. "I was trying to target the book to the Main Street investor, and to keep jargon to a minimum," Roth told me, and for the most part he succeeds.

Kevin's simple but well-diversified "second-grader portfolio," which he has kept, is divided among a U.S stock index mutual fund, an international stock index fund and a U.S. bond index fund. (An index fund tries to merely match the return of a market benchmark or index.) With their low costs - there's no need to research stocks or bonds to buy, and turnover and trading costs are minimal - index funds historically have outperformed most actively managed funds.

Many advisers today recommend investors also include a dollop of other types of investments or "asset classes" in their portfolios, such as real estate and precious metals. Roth argues investors should do so only if they understand that the purpose of adding them is to lower overall volatility, and if they're committed to sticking to their allocation for the long run. Continued...