Here's one reader's sticky situation:

Q: A coworker is always passing around a fund-raising form for something—wrapping paper for her kids’ school, a jump-rope-a-thon. How many of these charity drives must I participate in?

A: You’re not obligated to participate in any charity—whatever you sponsor or purchase is up to your discretion. However, if you have a particular soft spot for someone in the office, buying something for her child’s school is certainly a nice way to express it. Some people don’t participate in fund-raising sales unless they’re going to need a particular item anyway; wrapping paper is a good example. Instead of going to Sam’s Club, for example, you might as well help out little Susie Miller.

Read-a-thons and sponsored races are clearly less fruitful for the investor, but at least the amount given can be adjusted to any budget. Be sure to ask how many miles or laps the sponsee is likely to do, or if you can give a flat donation. My brother pledged a dollar a lap for the walk-a-thon at my son’s elementary school one year. Little did we know, the kids essentially ran around the perimeter of a tree planter, and Uncle Rod ended up owing $120. Not exactly what he had in mind when he signed up.

The point is, your total donation could amount to the price of a latte. But if you don’t want to give any amount, there’s nothing wrong with taking a pass. “I’d love to,” you could say, “but my husband and I are in lockdown mode with our finances right now. We’re really trying to spend only on the necessities.” And with that, if your coworker does anything more than give a quick wave and discreetly exit your office, go ahead and buy as much Sam’s Club wrapping paper as you can carry. Guilt-free.

Answer from Sally Schultheiss, a freelance writer who specializes in life and family issues, lives in Los Angeles with her husband and children Eddie, 6, and Jane, 4.