Wendy Gordon, General Manager, National Geographic's TheGreenGuide.com

It's back to school time, which brings the return of those nasty colds that travel from kid to kid through the entire class. Did you know the average American uses 50 pounds of tissue paper per year? That equals a lot of felled trees if every pound comes from virgin pulp.

That fact drove me to start buying recycled-content paper products. I've learned with time to look for the highest content of "post-consumer waste," or PCW:

Marcal products are entirely recycled, and although they contain a relatively low level of PCW content, that brand is the one most commonly found in conventional grocery and drug stores.

Natural food stores will provide you with a greater selection of products with a higher PCW content, offering brands like Seventh Generation, Earth First, and -- at Whole Foods only -- 365.

If you're really dedicated to the cause, online retailer Green Earth Office Supply sells a Finnish brand of toilet paper called Heron's, which is 100 percent PCW and even comes without the pesky, albeit recyclable, cardboard roll.

For a complete list of recycled-content (and chlorine-free) paper products, you can download thegreenguide.com's Paper Products Smart Shopper's Card.

Wendy Gordon, General Manager, National Geographic's TheGreenGuide.com

With severe to extreme drought conditions affecting parts of the U.S. and Australia, as well as elsewhere, I for one am eager to find ways to reduce my water footprint, not just my carbon footprint.

There are numerous ways to save water, but here's one simple that hadn't occurred to me until I read it in the Green Guide: Switch from liquid detergents to powders. Laundry liquids are mostly water (up to 80 percent). While the double and triple compact concentrates reduce that amount, it still costs energy and packaging to bring this water to the consumer.

So we can all save three ways by using powder detergents to wash clothes. The same holds for dishwashing detergents, when there's a choice, choose dry powders. For other water saving tips, check out thegreenguide.com.

Wendy Gordon, General Manager, National Geographic's TheGreenGuide.com

A new friend (whose wife just had a baby) was recently telling me about all the things they were doing to keep environmental contaminants out of their home. He asked me if I knew which houseplants were most effective at reducing indoor air pollutants. I didn't know the answer off-hand but was curious to find out.

I came upon a wonderful book by Dr. B.C. Wolverton, How to Grow Fresh Air. What I learned is, while plants can't cure major indoor pollution problems on their own, as noted in a recent Tip of the Week, they are an ideal antidote to the minor contamination introduced into our indoor environments through everyday household products and building materials.

Plants produce oxygen, add precious moisture and remove toxins from the air through the tiny openings in their leaves. In fact, as few as 15 houseplants in an average-size home can offer a significant reduction in the number of indoor contaminants.

This is not just folklore. In the 70s, the National Aeronautics and Space Administration, faced with the task of creating a life-support system for planned moon bases, began extensive studies on a fundamental question -- just how does the earth produce and sustain clean air? The answer of course is through the living processes of plants. Now, 30-plus years later, we know a great deal about the cleansing power of house plants. And powerful they are. Just consider the indoor air quality problems many commonly available and beautiful houseplants can help to remedy:

Formaldehyde: The Boston fern (Nephrolepi exalta "Bostoniensis"), Florist's mums (Chrysanthemum morifolium), the Gerbera daisy (Gerbera jamesonii) and the Dwarf date palm (Phoenix roebelenii) are all highly effective at reducing indoor levels of formaldehyde, a contaminant present in many household items (including particleboard, carpet backings, some grocery bags, facial tissues, paper towels and permanent-press clothing) and released by gas stoves.

Toluene/Xylene: Add an Areca palm (Chrysalidocarpus lutescens), the Moth orchid (Phalenopsis) and the Dwarf date palm to your indoor greenery, all of which are effective at removing xylene and toluene, harmful volatile organic chemicals which can be emitted from gasoline, adhesives, ceiling tiles, computer screens, paints, inks used in photocopiers, stains and varnishes, and upholstery among other common household products and materials.

And it's not just our material things. Our breath contains bioeffluents -- such as ethyl alcohol, acetone, methyl alcohol and ethyl acetate -- that also contribute to poor indoor air quality, particularly in a crowded classroom. The beautiful peace lily is remarkably effective at addressing these problems.

Other hardworking and beautiful indoor plants include bamboo palm (Chamaedorea), Chinese evergreen (Aglaonema), English Ivy (Hedera helix), the indoor dracaenas (Dracaena "Janet Craig," D. marginata, D. massangeana and D. warnekii), and the snake plant or mother-in-law's tongue (Sansevieria trifasciata laurentii).

When choosing houseplants, remember that many (including some of those above) can be toxic if ingested, so be extra careful if you have young children or pets in your home. Staff at the local garden center should be able to advise you on nontoxic choices; contact your local poison-control center for guidance (the phone number is listed in the front of your telephone book).

For a beautiful and authoritative reference to the cleansing power of particular houseplants, order How to Grow Fresh Air (Penguin Books, 1996, $18) from our online book store. And get more tips and advice on how to reduce or eliminate indoor air pollutants in your home at thegreen.guide.com.

My youngest was considering what he wanted to do the summer between his junior and senior years in high school. He’d thought he’d stay home, get a job and play lacrosse, in the hopes that this might put him in a position to be recruited for a college team. It seemed he was all set, but then he and a couple of friends started thinking about something altogether different: traveling far from home and volunteering.

Their imaginations took them to the farthest points on the planet, and involved some fairly outlandish job ideas, so with a bit of gentle steering from mom, they began to explore what their real options might be. My husband and I were ok with their traveling to a far away country as long as it was a relatively stable one (they were only 17), and as long as the organization they worked for was legitimate.

My son and his friends studied volunteer programs in Asia, Africa and the Americas, primarily through internet searches and word of mouth. At the same time, we asked a lot of friends with older kids and also a number of teachers about programs they’d researched and what they knew about them. The kids then contacted the ones they were most interested in. They settled on an agency that ran an orphanage in Llasa, Tibet and were in need of teachers.

The program they chose was geared for college kids and adults, so it did little to coddle the volunteers -- or his anxious parents. There were no pretty brochures or thick packets of forms sent to us to prepare them for the trip, just what the organization provided on their web site.

Wendy Gordon, General Manager, National Geographic's TheGreenGuide.com

There's no place I'd rather be in July than our garden.

I feel pretty lucky to have this garden, all 40 x 30 square feet of it, which is just a couple dozen yards from a 100+ year-old farmhouse we have in the western Catskills. It produces an abundance of vegetables from early June through late September. There's no evidence proving that locally grown is better for you, or "more nutritionally complete," but no group of scientists are needed to inform me that my fresh-from-the-garden vegetables taste a whole lot better than those that have shipped thousands of miles from farm to fork.

I also like that I haul my dinner greens to the kitchen myself -- no car, not even a bag. According to Joan Gussow, Columbia University nutritionist, shipping a strawberry from California to New York requires 435 calories of fossil fuel but provides the eater with only 5 calories of nutrition.

Gardening is something my husband and I enjoy. The kids seem to always disappear when it's time to plant, mulch, or weed. But they are always at the ready when harvest time comes around, which starts early in our garden --when perennials, including rhubarb and asparagus, come bursting through the cool soil at the same time we're planting the first early season peas, beans and lettuce seeds -- and runs pretty much straight through October.

Our approach to gardening is a bit haphazard, but we have gotten better at picking seeds that are right for our region. Most catalogs offer a zone chart and other keys; Seeds of Change has the best charts among the catalogs we get, showing how much sun and water certain plants need and in which zone they are best suited.

Then there is the matter of which seeds to choose. We're not purists about it, but we do try to buy organic seeds whenever there is an option. Conventional seeds might have been harvested from chemically grown plants, and they also may have been treated with insecticides or fungicides prior to sale. We also try heirloom varieties that are from our region whenever we come across them. Even the major seed catalogs, such as Burbee, offer a number of organic and heirloom varieties.

You don't need a big yard or even a yard to plant a garden. A small potted garden on a terrace or sunny apartment window sill can provide a year round bounty. As part of my work on The Green Guide, we've come up with lots of tips on starting a vegetable garden, including a list of companies offering organic and heirloom seeds.

Wendy Gordon, General Manager, National Geographic's TheGreenGuide.com

I'm a mom with two college-aged kids. Correction, I've got one son in college and another who just graduated. The older one and I just packed up his dorm room of 4 years of college life and brought most of it home. I'm a "less is best" type, and so set right to work sorting what's to be kept, what's to be replaced and what's to pass along.

Neither one of our kids are overly consumptive, but the new grad could outfit a small village with the commemorative t-shirts he collected from the many social and sporting events he'd attended over 4 years. That hopefully is what's in store for their second life, following our wardrobe purge this week. The local thrift shop is the perfect resting stop for a lot of our clothes, once we've grown out of or beyond them.

The equipment he'd accumulated formed another small mountain. After 4 years, the laptop sorely needed replacing and so for a joint graduation/birthday gift, his dad and I got him a nice new computer. But while one computer had served him well throughout college, he managed to lose several phones and iPods along the way, so one desk drawer was dedicated to the power cords, extra batteries, and parts that come with every new devise. Not sure why, but he used the same drawer to collect empty ink cartridges. This is all good however because we boxed it all up and will take it to the local recycling center. They recover what they can and recycle the rest.

Clothes were packed neatly, winter and summer things separately. We'll wash and put away some things for longer-term storage as his first real job will take him to LA, where he won't need so many heavy things. The son still in college returned most of his textbooks to the university store for resale. The graduate preferred to keep his. That was fine. He had collected some amazing books on art, literature through the ages, philosophy, religion, and history. These possessions seemed like keepers.

He's back in his room at home, a pretty small apartment, but everything we're not giving away manages to fit (more or less). In a month, he'll be heading to California for a job and his first post-college apartment. He's bound to accumulate possessions with time, but I'm hopeful he's picked up just a little bit of his mom's sense of the value of things and the virtue of "enough."