For many years, my mother taught in a sunny, spacious classroom in our neighborhood school in St. Louis. She was such a wonderful teacher that every year parents lobbied the principal to secure spots for their kids in my mom's class.

I used to tell her that she should be proud that she was in such demand, but my mom abhorred the fuss. Ironically, what she did feel good about was her 403(b) retirement plan. When she retired, she was pleased with the cash she had squirreled away in her tax-sheltered annuity.

As it turned out, my mom was a master at motivating fourth-graders, but she knew less than a dilettante about what was inside her retirement account. Her 403(b) account did grow over the years and ultimately generated monthly checks when she finally called it quits and boxed up a lifetime of books, apple knickknacks and bulletin board decorations. What my mom didn't know was that her annuity, which was offered by a big-name insurance company, was loaded with unnecessarily high fees that squished her nest egg.

Unfortunately, millions of teachers and others who invest in 403(b) plans are just as oblivious as my mother. I'm not wildly speculating on this one. All you have to do is take a gander at where teachers are stashing their retirement money to know they haven't done their own homework. Only 19 percent of teachers' 403(b) cash, according to a Spectrem Group survey, is invested in mutual funds. In this $607 billion market, the vast majority of teachers have embraced expensive annuities.

Since our brains seem to be hard-wired toward finding the best deals - think about all those folks who will be pressed against the doors to Wal-Mart the morning after Thanksgiving to snatch up holiday specials - you may be puzzled why teachers eagerly embrace what is far worse than that third helping of pumpkin pie. They stick with pricey annuities because that's what the insurance agents and brokers are peddling in school lounges.

These annuity reps seem believable and earnest and, unlike students, they keep their shirts tucked in. In contrast, you won't find the low-cost 403(b) players, most notably Fidelity Investments, T. Rowe Price, TIAA-CREF and Vanguard Group, chasing anybody down the hall.

Because the stakes are so high, you need to know what's inside your 403(b) plan. Are the investment choices you made any good? What kind of fees are you paying? You may find that your 403(b) account balance is groaning under the weight of sales commissions, investment and insurance expenses, subaccount fees, wrap fees, surrender charges, and who knows what else. Once you start poking around, the odds are you won't like what you discover. Continued...