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I Will Be Good to the Planet. I Will Be Good to the Planet. I Will Be Good to the Planet.Are blackboards more environmentally friendly than whiteboards?

By Nina Shen RastogiPosted Tuesday, Sept. 8, 2009, at 3:37 PM ET

Over the summer, the high school where I teach had a complete makeover—which included replacing all our old chalkboards with whiteboards. I'm happy not to be breathing in any more chalk dust, but with all those plastic pens I'll be throwing away, is the new system really any better for the environment than the old?

Veteran teachers will debate endlessly the merits of chalk vs. dry-erase. Some insist that their preferred system has pedagogical benefits (one science teacher told the Lantern that she wrote more slowly with chalk, giving students more time to absorb difficult concepts), while others appreciate its feel or smell. With apologies to both camps, let's assume that blackboards and whiteboards are completely interchangeable with respect to teaching, so we can figure out which is better for the planet.

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The Lantern was surprised to discover that the boards themselves are going to be more or less the same whether you're writing in chalk or dry-erase ink. Until the 1960s, chalkboards were made from slate, which is extracted from the earth through quarrying. These days, though, a blackboard consists of a steel core with a porcelain overlay—just like most wall-mounted whiteboards. So the primary comparison here comes down to a face-off between chalk sticks and markers.

Chalk is a relatively simple product: Start with either calcium sulfate or calcium carbonate—the main sources of which are gypsum and limestone, respectively—mix with water and pigments, extrude into stick form, and then bake. All these steps require energy, and quarrying gypsum and limestone has the potential to cause air pollution.

Dry-erase pens, on the other hand, have a number of components—plastic barrels, caps, filaments, and ink—so they're going to have a much more complicated life cycle. As with mechanical pencils—the subject of the Lantern's last back-to-school column—the main issue here is the plastic: Plastic manufacturing requires petroleum, a nonrenewable resource. And at the end of their lives, whiteboard markers are virtually guaranteed to end up in the trash bin. Even if you felt motivated to disassemble your pens so you could dispose of them more responsibly, it wouldn't do much good—most markers don't indicate what kind of plastic they're made out of, and those that do are often polypropylene, which generally isn't recyclable.

Chalk, however, can theoretically be a very low-waste product, especially if you use a chalk holder that allows you to keep using the sticks until the bitter end. (And once you're left with nothing but nubs, you can take them home and use them for other purposes—like keeping your silver from tarnishing or removing grease spots from your clothes.) Chalk also tends to be packaged much more simply, which means less trash headed for the landfill. There is the issue of chalk dust, which can trigger allergies and aggravate asthma. Some teachers also report that chalk dust can muck up electronic equipment—that means more cleaning supplies, plus the potential need for more frequent replacements. Dry-erase pens can produce dust, too, though, and the residue left on the board often requires special cleansers.

Many chalk adherents claim that chalk is cheaper than its competitor, which would certainly boost their green cred. Money saved on writing implements, after all, can be put toward other, environmentally friendly classroom upgrades—like swapping out T-12 fluorescent bulbs for the T-8 variety, which the Department of Energy estimates can save up to 30 percent (PDF) of a school's lighting energy. It's not obvious, though, that the math works out in favor of chalk. It's true you can get a box of 12 colored chalk sticks for just 99 cents on OfficeDepot.com, while a four-pack of colored markers costs $5.39. But some veteran teachers say it is possible that a single pen would outlast 16 sticks of chalk, making it a better value overall.

To properly compare a stick of chalk with a disposable dry-erase marker, we'd need to have better data on how the manufacturing impacts stack up, since they're likely to be the biggest factor in the equation. The pen maker BIC, for example, says 90 percent of the environmental impacts of its Cristal-brand plastic ballpoints stem from the production phase. Since your school has already made the wholesale switch to whiteboards, reusable pens—like AusPens and Artline's ECO marker—are probably your best bet, provided that the ink refills and replacement nibs for these products aren't themselves overly packaged.

Of course, as an individual teacher, you might not have much say in your school's procurement policies. And having once been a high-school teacher herself, the Lantern knows how whiteboard pens have a tendency to migrate from classroom to classroom. If you have the time and the resources to buy your own pens—and then ensure that they're used properly and not chucked as soon as they run out of ink—the Lantern heartily applauds your efforts. But if that's unrealistic, there are plenty of free, easy things you can do to reduce your classroom's footprint.

For example, you can shut off all the lights if the room is going to sit empty for more than a few minutes. According to Pacific Gas and Electric, up to between 8 percent and 20 percent of a school's lighting energy can be saved this way. Keep computers, printers, televisions, and other electronics powered down when not in use. Better yet, involve your students in your monitoring efforts. If you can help them understand how small choices made in individual classrooms can add up on an institutional level—a lesson that they'll hopefully take into adulthood—you'll be doing a lot more for the planet than you would by personally choosing one type of writing utensil over another.

Is there an environmental quandary that's been keeping you up at night? Send it to , and check this space every Tuesday.

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Nina Shen Rastogi is a writer and editor in Brooklyn, N.Y.

Illustration by Rob Donnelly.

COMMENTS

The Smartboard allows a teacher the freedom to integrate computer- and internet-based lessons; you can click on icons on the Smartboard just like you would a computer monitor, and everything you write with the special pens can be converted to electronic text.

I have a StarBoard in my classroom, which isn't the same thing (it's really just a glorified overhead projector), but I have seen the Smartboards and I envy those who have them. They're pretty danged cool, and they make this debate more or less pointless, in my opinion. The Smartboard integrates video, computer technology, and the simple whiteboard all in one, so you can conceivably do away with all that other stuff that clutters a classroom's corners when not in use.

-- BritBailey
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But what about the water? I can go weeks without having to take the ol' sponge to the whiteboard, but chalkboards needed to get washed every day.

-- Utz_the_Crab_chip
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If you were simply to ask which is worse - between extracting crude, refining propane, processing that into propanols, further processing these into plastics and finally manufacturing stuff... vs quarrying limestone into lime and using that lime with gypsum to form chalk. Chalk is probably the loser.

Lime plants are second only to cement factories as the biggest point-source emissions in the country. Lime has a VERY big carbon footprint. Of course, plastic does too, but as Baltimore pointed out the stuff that is thrown away isn't really a concern... the only concern is the manufacturing of the replacement.

I believe I recall that lime production emits between ~0.5 tons of CO2/ton of lime. Plastic manufacturing generally emits ~6 kg CO2/kg of plastic. Therefore, all other things being equal, as long as the pens consumed in a given time frame (say over the course of a year) weigh less than 1/12 the weight of the chalk that is consumed over that same time frame... then chalk loses. I would guess that one stick of chalk weighs slightly more than one pen, so as long as the pen outlasts ~10 sticks of chalk (this is a guesstimate), then the pens win.

-- Tundrayeti
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One oft-overlooked consideration in this debate is that several types of colorblindness cause difficulty in reading blackboards. Blackboards tend to be dark green, one of the most common problem colors for the colorblind. Most colored chalk appears either invisible or so faint that words cannot be deciphered. Even white chalk can disappear into the blackboard if the lighting conditions are bad, such as glare from an open window.

Whiteboards aren't perfect either because teachers tend to use colored markers. But there should be no problem seeing black or blue marker, and even red, green, or yellow are easier to see against a white background than against a green background.

Considering that about 10% of the male population is colorblind, a lecture hall that has 200 students and a 50-50 gender distribution should have about 10 colorblind students. They should be taken into consideration in this issue.

-- MTB1
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