Now You See It…

now-you-dont This paper disappears in water before your very eyes, leaving the letters floating free. It’s the ultimate aqueous word scramble!

I was very intrigued when I spotted this dissolving paper in Educational Innovations’ online catalog. I’ve certainly seen the floating letter experiments with Skittles and M&Ms, but I’ve never seen anything like this paper! It’s made of sodium carboxyl methyl cellulose, a non-toxic substance that dissolves quickly in hot or cold water. Each sheet is 8.5″ x 11″. You can buy the sheets in packs of 15 for $7.95, packs of 30 for $13.95, or, if you want to vanish a whole novel, you can get 100 sheets for $42.50.

dissolving-paperThe paper is about half the thickness of standard office printer paper, but it went through both of our office printers and the copy machine with no tearing or jamming. Granted, I was just printing 1 sheet at a time. I did try 3 pages in a row on our most trustworthy office printer. Unfortunately, it had trouble grabbing the thin paper and actually missed the final sheet of the print job entirely. I was waaaay too chicken to try multiple sheets in the copy machine.

The product description stated that this paper works with “most laser printers and copiers.” But we took it a step further and also tested an inkjet printer, Sharpie permanent marker, roller ball pen ink, and ballpoint pen ink.

First, the laser jet printer. I filled a dish tub with a couple inches of room temperature water a dropped the paper in. It floated for a just moment, and then started rapidly dissolving. In a few seconds, it was reduced to a thin, almost transparent, paper-shaped film.

The package recommended giving the water a gentle stir, so I poked a drinking straw in the solution. It started breaking up, dissolving further, and yes! The letters started floating! How long do the letters remain on the surface of the water? A long time! I left them in the dish tub overnight, and they were still happily floating the next morning.

laserjet-testSecond test, copy machine. The letters printed considerably lighter on the page (this was a toner thing with our copier, not the paper). But that didn’t impair the letters from floating on the water like little alphabet ducks!

copier-testSo our laser jet printer and the copy machine worked. What didn’t work? Our inkjet printer. First of all, it blotted the paper during printing…

inkjet-blotchAnd when it came to the water test, the letters just disintegrated:

inkjet-testThe same applies for Sharpie permanent marker:

sharpie-testRoller ball ink and ballpoint ink also broke apart. The ballpoint ink shredded immediately (you can just see the sentence “Will ballpoint pen work?” at the bottom of the image below). Roller ball, I am surprised to report, held out a little longer.

roller-and-ballpoint-testIt was sort of cool. The roller ball ink blurred, sunk a little, and then just hung in the water (which is when I snapped this Instagram pic). Eventually, however, the roller ball ink went the way of the ball point, Sharpie, and inkjet. It dissolved into a black smudgy mess.

It’s important to note that for all of these tests, the paper didn’t dissolve entirely. There was a little cloud of solution that started hanging around the bottom of the dish tub. The more paper I dissolved, the cloudier the water become. So if you’re going to do this with a bunch of kids, you will definitely need to change the water every so often.


Being the incredibly mature people that we are, we decided to test the paper in the toilet. It worked. Of course it worked.

toilet-testBut no matter where you’re dissolving this paper – a dish tub or a commode – the letters do float apart very quickly. So leaving a secret message for someone isn’t really going to work (unless they’re standing right next to you and reading quickly). But this would be a fantastic way to introduce the concept of the anagram. Or jump-start a discussion about biodegradable materials. Or, just experience the fun of watching a sentence you’ve written slide apart and swirl across the surface of the water. Magic!

These Butterflies Can Book

these butterflies can bookRecently, while in Brooklyn, I wandered into a little toy store called Matt & Juliette. There, I discovered some neat-o wind-up butterflies by Seedling. The clerk at the toy store explained that some people like to put the butterflies inside birthday cards. When the recipient opens the card, the butterfly flutters out. If it works for cards, I thought, it’ll totally work for books! I immediately purchased a pair to test out. They retail for $3 each and come in 4 different colors and styles.

magic butterflies by seedlingAs you can see, the toy is pretty simple. You hold one half and twist the other half. This motion winds the 2 rubber bands, which ultimately propel the toy skyward.

butterfly toyThe directions warned that winding the rubber bands too tightly could cause them to snap. This is true. Over the course of 20 test flights, we broke 2 rubber bands. But there are two spare rubber bands in each package, so no problem! Alas, one of the plastic hooks on the smaller butterfly snapped within 5 minutes, rendering the toy useless, but the other one held out just fine. Ready to see a butterfly in action?

There’s no denying it. It’s fun to have a butterfly sail out of a book. But the toy is erratic. Sometimes it flutters around the table, sometimes it dives to the floor, and sometimes it tears out of the book and zooms away like a bird.

There is absolutely no way to predict, or manipulate, the butterfly’s path out of book. Especially when it decides it wants to attack you.

The erratic flying made me wonder if this toy would freak out kids. So I tested it out on my unsuspecting children (ages 5 and 7). They loved it! There was no flinching or shrieks of alarm when a butterfly suddenly flew out of the book. In fact, they took turns winding it up and releasing it from their hands. This made me realize that the toy is a simple machine, and might work at a STEM program too.

In short, for $3, this is an inexpensive piece of magic for your next story time or program. Just make sure to buy extra butterflies in case the plastic breaks. Happy flying!

A Day in Digitopolis, Part II

Radiance by Matt ElsonWho knew infinity could be so beautiful? I’ve returned with Part II of the Digitopolis event post (Part I can be found here) and thought I would start it off with one of the stars of the show! The above image was taken inside an Infinity Box, one of multiple creations by Los Angeles-based artist, Matt Elson. Matt’s boxes have been exhibited at colleges, science centers, festivals, and museums. He generously loaned us two (titled Radiance, and You & Me Together) for our math event.

You and Me Together by Matt ElsonThe boxes are designed to be infinite, interactive environments that play with your perception and inspire inquisitiveness and wonder. They were in constant use during the event, and there were lots of shrieks of amazement, enthusiastic explosions of “Cool!” and long, drown out utterances of “Woooooow…”

infinity marissaDigitopolis was not without its celebrities too, including the King of Numbers himself. I speak, of course, of the Mathamagician.

mathamagiciansThat’s real-life mathamagician Brent Ferguson on the right, grinning away under the pointy hat covered with equations. He’s math faculty at the Lawrenceville School, and in 2013, he was awarded the National Museum of Mathamatics’ Rosenthal Prize for innovation in math teaching. On the left is Dr. Dan Fishman, a high school math teacher, who, like Brent, has unbridled enthusiasm for all things math.

Together, Brent and Dan staffed the “Ask the Mathamagician” table. Kids could walk up and ask them any question they could possibly think of involving math. We had prompt cards on the table to get things started:

Why do you like math?
What’s an irrational number?
What’s the biggest number there is?
Why is math important?
Why does a negative times a negative equal a positive?
Is zero a number?
What’s a perfect number?
What’s that crazy math thing with the exclamation point?
What’s an imaginary number?
Know any good math jokes?
What’s your favorite equation?

Brent and Dan also brought a whole bunch of math toys and puzzles with them. It was an irresistible treasure trove of numerical goodies.

mathamagician 2Also at the Mathamagican’s table were three Digitopolis “tourism” posters for families to take home (the posters were inspired by this fantastic NASA concept). The first two posters are by Princeton University senior, Aliisa Lee. The third poster is by freshman Demi Zhang.

city poster by aliisa leemines poster by aliisa leeevent poster by demi zhangA quick word about the Mathamagician’s costume. The robes and hat were made by freshman James Jared, who ingeniously modified this Jedi robe. Then Casandra used silver and gold metallic fabric markers to draw real, honest-to-goodness math equations on them. We snapped a couple shots so you can get the full effect!

robes 2robes 1The Mathamagician wasn’t the only celebrity in Digitopolis that day. Does this gentleman look familiar to you?

albert einsteinYup, it’s Albert Einstein. Or rather, professional reenactor Bill Agress playing Albert Einstein. Mr. Einstein circulated the event floor, chatted with kids, answered questions about his life and work, tried an activity or two, and posed for pictures. And yes – he wasn’t wearing any socks.

In addition to being one of world’s most famous theoretical physicists (and no slouch at mathematics either), did you know that Einstein was a resident of Princeton? He emigrated here in 1933 to join the faculty of at the newly-created Institute for Advanced Study.

The Historical Society of Princeton put together a terrific mini-exhibit on Einstein in Princeton (my favorite is that photo of him wearing the fuzzy slippers). Families were invited to take home a map of notable Einstein haunts around town as well.

historical societyThey also whipped up an Einstein quiz for kids to try (the answers, by the way are B, A, B, C, B, C). The prize was a cool little puzzle. I found some terrific ones at Oriental Trading Company (the ones below are from the “Mind Teaser Game Assortment”).

maze prizesElsewhere in Digitopolis, another math wizard was hard at work. This is Emile Oshima, a junior at Princeton and master of the Japanese abacus. Next to him is senior Rei Mastsuura.

abacus races 1In addition to having Emile and Rei teaching kids how to use an abacus, Emile raced kids (and parents!) armed with electronic calculators to see who could reach the product of 3 x 3 multiplication problem faster. Emile always won. He was lightning fast!

abacus races 2Meanwhile, at another event table, another calculator was keeping kids busy. But this calculator was rather…odd.

crazy calculator 1The “Crazy Calculator” was designed by the Princeton Society of Women Engineers using 2 Makey Makey sets. Have you seen Makey Makey? It’s pretty awesome. Each set consists of wired alligator clips, a small central board, and computer software.

Attach the alligator clip to anything that conducts electricity, and you can do all sorts of crazy things. Turn bananas into a keyboard, or use Play-doe like a video game controller. The Women Engineers used all sorts of things to build their calculator – tin foil, wet sponges, water, metal objects, shaving cream, flowers, even high fives!

crazy calculator 2Interspersed with the other event tables were 5 “Pop Up History” activities that tied together math and history. These tables were designed to be simple, stand-alone, and un-staffed.

global counting 1At “Global Counting,” kids could see diverse numerical systems on a big display board (the book Go Figure: A Totally Cool Book About Numbers (DK, 2005) was very helpful in this regard). Then, kids copied their favorite number system on a 3.5″ x 17″ strip of paper, and used yarn to turn it into a little scroll.

global counting 2At another table were Möbius strips, a must-have for any hands-on math event. Discovered in 1858 by German mathematician August Ferdinand Möbius, the strip demonstrates how a piece of paper can have only one side! All it takes is a 2.5″ x 28″ piece of poster board, tape, and some instructions.

mobius stripsAnother hands-on math must-have? Tangram puzzles. Originating in China, tangram puzzles were first introduced to Europe in the 19th century. There are plenty of inexpensive tabletop tangrams out there, but we decided to splurge on some giant foam floor size versions (thinner ones purchased from SimplyFun, chunkier ones from Fat Brain Toys). Later, these were donated to a local non-profit family shelter.

tangram puzzlesThe fourth Pop Up History table was called “Tally Hides.” Some American Indian tribes kept track of important things by making tally marks on animal hides and tree bark. Definitely a cool way to count!

tally hides 1Before the event, we cut 9″ x 12″ pieces of brown paper into the shape of a hide. During the event, kids wrinkled the paper, flattened it out, and used markers to draw the wildlife they’ve seen around their homes and town. Then, they estimated how many times they’d seen each critter, and made a tally mark next to it. The project is originally from The Secret Life of Math (Williamson Books, 2005).

tally hides 2The final history table was called “Tile Tessellations.” Decorating surfaces with tiles spans many cultures, and many centuries. But did you know that the geometry in Early Islamic art was so intricate, it was unrivaled for over 500 years?

tiles 1Kids put their tiling and tessellating skills to work by gluing 3/4″ paper tiles to a 6″ x 6″ square of tagboard. This project was really bright and beautiful.

tiles 2That’s it for history – how about some games? JaZams, our local family-owned toy store hosted a event area called “The Game is Afoot.” JaZams chose 8 math games for various age ranges (you can see their official selections here), and set each of them up on a series of tables. Kids could drop by to play the waaaaay popular Rubik’s Race…

game is afoot 1Or entire families could take a break and play Number Ninjas.

game is afoot 2Heck, maybe you could even beat Einstein at Qbitz! After the event, the games were donated to a local non-profit family shelter.

games is afoot 3For the musically adventurous, there was “Musical Fractions,” an activity composed by senior Matt Smith and freshman Demi Zhang. Kids used percussion instruments (assorted floor drums, wood blocks, maracas, a wooden fish, claves, and sand blocks) to learn how to play, and recognize, wholes, halves, quarters, and eighths. They also learned about musical structure and patterns.

musical fractionsEach instructional session ranged between 10 to 15 minutes. I wasn’t able to catch an entire one, but I did manage to grab a few seconds of this one. Just listen to those fractions!

I have one last thing to share with you. Team Digitopolis in their awesome event t-shirts.

front of shirtsAt big events like this, my staff and I wear costumes so that people can find us quickly in the crowds (helloooo Victorian Steampunk spelunker). For Digitopolis, however, I decided to go with t-shirts, and asked student artist Aliisa Lee to design them. Here’s a closer look at her beautiful cityscape!

digitopolis by aliisa leeOn the backs were our favorite numbers. Let’s hear it for 9, 2, and 11! Woot woot!

back of shirtsI’d like to send a million, trillion, zillion, googolplex thanks to everyone who made this event possible, and who generously gave their time to make math fun, approachable, unusual and fun. An extra shout out to the Princeton University students, and the student athletes who volunteered so energetically and enthusiastically! Thank you so much, everyone!