 At left in the back is a fresh spinach leaf that has been treated with trehalose, frozen and defrosted.. The droopy one has been frozen and defrosted without trehalose. It's what is giving us hope that we may soon be able to defrost a salad. When it comes to preserving a fresh taste in food to be eaten at some later time, nothing beats freezing it. That was the discovery made by Clarence Birdseye in 1924. He had been working in northern Canada and noticed that fish caught by the native Canadian Inuits froze almost instantly in the frigid winter air. It was just as delicious when cooked and eaten months later as it was on the day it was fresh. Birdseye figured that if food was frozen quickly at very cold temperatures, large ice crystals couldn’t form to damage the food and make it mushy. His flash-freezing process made him very rich. The problem isn’t so much the freezing of food as what happens when it’s defrosted. See for yourself. Stick a stalk of celery in your freezer. The next day defrost it. Want to eat it? Compare it to a fresh unfrozen stalk. The perky structure of fresh celery is destroyed by ice. Water has the very unusual property of expanding and taking up more space when it changes into ice than when in a liquid state. That’s why ice cubes float and frozen unopened soda cans bulge. Expanding ice crystals destroy the cell walls of plants. Quickly freezing fresh food keeps the ice crystals smaller than slower freezing, but they are still large enough to destroy the cell walls of delicate vegetables like spinach or lettuce. But if you defrost frozen spinach from the supermarket it is beyond limp. So a salad you can defrost and serve as if it were fresh has seemed like an impossible dream. Federico Gomez, a Swedish scientist, is working to change this. Like Birdseye he took a close look at nature, specifically at plants that stay alive in very cold climates. He discovered that they contain a sugar called trehalose (tree-HAL-ose) that works like a natural antifreeze. Could he find a way to get trehalose into spinach leaves? If so, would the trehalose protect the structure of the spinach and keep it crisp after defrosting? This picture shows the results. The leaf on the left was treated with trehalose. The one on the right was untreated. He froze and defrosted both. The treated leaf is as crisp as if it had never been frozen! Just because there is success in a lab doesn’t mean a defrosted salad will show up on your dinner plate any time soon. But these results are enough to keep the research going. Move over Clarence Birdseye!
 Cobb has revised her classic book, Science Experiments You Can Eat. While doing her research, she came across this work of Frederico Gomez. She bought trehalose on line and soaked some slices of parsnip and zucchini in a trehalose solution, hoping that the sugar would be absorbed by the plant cells. But when she froze them and defrosted them, it didn't work. Dr. Gomez got the sugar inside the plant cells by removing some water from between the cells in a vacuum chamber, soaking the leaves in a trehalose solution (which moved the sugar into the spaces outside the cells) and then exposing the leaves with a mild electric shock to get the sugar through the cell walls. Vicki didn't have the equipment to do all this but she tried anyway. The book was published in 2016. Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more. MLA 8 Citation Cobb, Vicki. "Why You Can't Defrost a Salad...Yet." Nonfiction Minute, iNK Think Tank, 11 01 2018, www.nonfictionminute.org/the-nonfiction-minute/ Why-You-Can't-Defrost-a-Salad-Yet. 
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Booker T. Washington was an African American educator; Julius Rosenwald, a tycoon descended from an immigrant. Together, they planted the seed for thousands of public schools in rural communities during the segregation era In 1881, the formerly enslaved Washington founded Tuskegee Institute in Alabama. Washington held the controversial view that Blacks should focus on economic and educational progress rather than equal rights. At the same time, he advocated for Black businesses and secretly funded civil rights lawsuits.
n 1912, Julius Rosenwald, the president of Sears, Roebuck and Company, joined Tuskegee Institute’s board of trustees. Rosenwald opposed racism and wanted to use his fortune to help others. Washington suggested funding schools in rural African-American communities, many of which were still using ramshackle Freedmen’s Bureau facilities. From 1917 to 1932, the Rosenwald Fund awarded seed money—matching grants averaging $600—to construct more than 5,000 schools in 15 states. Communities had to raise additional funds, secure land and build the schools using blueprints from Tuskegee’s architecture department. The residents also bought supplies, fuel, and sometimes, school buses. The grants stipulated that the white community had to contribute to the building projects as well and that the state had to maintain the new schools.  In some areas, Rosenwald schools were the first educational institutions open to African Americans. Most Rosenwald schools lacked electricity or indoor plumbing and relied on hand-me-down furniture and textbooks from whites-only schools. Despite limited resources, Rosenwald schools were beacons of educational opportunity for generations growing up in the segregated South. After integration, the schools closed and most were torn down. The National Trust for Historic Preservation has listed the remaining structures as endangered historic places. The Rosenwald schools’ rich legacy offers lessons about community, anti-racism and the value of education. Poem: Taking Root (from Dear Mr. Rosenwald) The church deacons voted to give an acre Of land for a new school. Space For a building, playground and garden. Land that would have been used for graves. Now, a seed is sown instead.
 Carole Boston Weatherford, a Newbery Honor author, wrote the picture book Dear Mr. Rosenwald, an NAACP Image Award finalist and Golden Kite Honor winner illustrated by C. Gregory Christie. 
Imagine Earth as a button. I don’t mean you’re going to sew it onto your shirt. But imagine the planet Earth shrunk to the size of a button. (Of course Earth is not flat like a button but we’re giving our shrunken Earth the same diameter as a shirt button.) Go ahead and draw a circle around a shirt button. Call it “Earth.” Suppose you wanted to draw Jupiter, the largest planet, at the same scale as this micro-Earth. That means you’re going to shrink it to the same fraction of its original size as our button-Earth. What size would little Jupiter be? One way to find out would be to calculate how many times bigger the real Jupiter is than the real Earth. Earth’s diameter is about 8,000 miles (13,000 kilometers). Jupiter’s is about 88,000 miles (143,000 km). Divide the size of Jupiter by the size of Earth to see that Jupiter is about 11 times bigger. So, since Jupiter’s diameter is 11 times that of Earth’s, put 11 buttons in a line to show the diameter of Jupiter. Then draw the circle that represents Jupiter. If you don’t have 11 buttons, just look at the picture. Did you think the Earth was a big place? Look at it compared with Jupiter! But what about the sun? The sun’s diameter is about 865,000 miles (1,400,000 km). That means it’s almost 10 times bigger than Jupiter. Can you find a way to draw a circle 10 times the size of our Jupiter? We’ve drawn part of it for you, on the same scale as our button-sized Earth. On the picture, it’s labeled “our arc.” (An arc is part of a circle.) Looking at the arc, you can imagine the rest of the circle and compare the sun to Jupiter and Earth. A minute ago, you thought Jupiter was big. Now it looks shrimpy compared to the sun! But is the sun really gigantic? Do some research to find out the size of a red giant star like the strangely named Betelguese (pronounced “beetle-juice.”) Figure out what it looks like compared to our sun, which is a medium-sized star. You may be amazed at the difference. And you thought the sun was big! Is anything truly big? Is anything truly small? Or does that depend on what it’s being compared to?  If the Earth were the size of a button, Jupiter’s diameter would equal eleven buttons because the diameter of Jupiter is eleven times that of Earth. Both images are by Marissa Moss, the illustrator of David M Schwartz's book, G is for Googol.  Extend “our arc” to complete the circle and you’ll see what the sun would look like if the Earth were the size of a button. (An arc is part of a circle.)  G is for Googol: A Math Alphabet Book is a wonder-filled romp through the world of mathematics. For more information, click here. David Schwartz is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more. MLA Citation Schwartz, David M. "If the Earth Were a Button." Nonfiction Minute, iNK Think Tank, 16 Jan. 2018, www.nonfictionminute.org/the-nonfiction-minute/ If-the-Earth-Were-a-Button.  
Most disasters are a cascade: small failures and minor circumstances, one leading to another, blossom into a cataclysm. On January 16, 1919, a cascade of tremendous size was poised above Boston’s North End. The weather was one factor: unusually warm for winter. Purity Distilling Company fermented and distilled molasses to make rum and alcohol. The 18th Amendment to the United States Constitution, prohibiting sales of alcoholic beverages, was due to be passed the very next day. This may have prompted Purity to collect as much molasses as possible. The enormous tank holding the molasses was about 50 feet tall and 90 feet in diameter, holding 2,300,000 gallons. It was poorly built of thin steel painted brown to hide its leaks. Local families often collected some of the dripping molasses to sweeten their food. The unseasonably warm temperature quickly rose from 2° F (-16.7° C) to 40° F (4.4° C), expanding the liquid, and natural fermentation produced CO2 increasing tank pressure. Just after noon, North End families felt the ground shake and heard a sound like a machine gun— the tank’s rivets popping out. The big tank exploded, sending a 25-foot wall of molasses roaring down the hill toward Commercial Street at about 35 miles an hour. In front of the molasses went a blast of air that blew some folks off their porches and tumbled others along the street like rag dolls. Homes and buildings were destroyed, smashed from their foundations. Horses pulling wagons were swept away. The steel girders of the Boston Elevated Railway were buckled, knocking a rail-car off the tracks. Twenty-one people were killed and more than a hundred were injured. Many were saved by Massachusetts Maritime Academy cadets who rushed off their docked training vessel and plunged into the brown goo to rescue people. It’s difficult to know how many dogs, cats and horses died. As you can imagine, the clean-up was awful. Firehoses from hydrants and harbor fireboats washed away as much as possible. Boston Harbor was brown for months. Sightseers tracked the goo back to homes, into hotels, onto pay-phones and onto doorknobs. Everything Bostonians touched was sticky for months. Some say that on a hot summer day along the North End’s docks, the sickly sweet smell of molasses lingers. Bostonians can smile at the Great Molasses Flood now, but in January of 1919, that cascade of disasters was deadly serious.  Aftermath of the disaster; photo by Globe Newspaper Co. (Boston Public Library)
Jan Adkins is an author, an illustrator, and a superb storyteller. Read about him on his Amazon page. He is also a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more. MLA 8 Citation Adkins, Jan. "The Great Boston Molasses Flood: How Can a Tragedy Sound Funny?" Nonfiction Minute, iNK Think Tank, 19 Jan. 2018, www.nonfictionminute.org/the-nonfiction-minute/ The-Great-Boston-Molasses-Flood-How-Can-a-Tragedy-Sound-Funny? 
Henry Ford is famous for founding the Ford Motor Company in 1903. He built the Model T and changed America from a horse-and-buggy country to a nation of paved roads and honking cars. Yet most people don’t realize that Henry also transformed American agriculture with his work with soybeans. During the Great Depression of the 1930s many farmers lost their farms or left crops to rot because they cost too much to harvest. Henry thought this was a waste, so he began to look for ways that common crops could be used in industry. He built a laboratory at Greenfield Village, and studied the chemical makeup of every fruit, grain and vegetable. After two years, Henry found the: the soybean! It was the perfect crop to use in his factories because it was packed with oil and protein. The oil made a paint that was glossier, less expensive, and dried to a harder finish than other coatings. By 1934, every new Ford boasted a coat of soybean paint. The soy protein, mixed with a chemical resin, created a sturdy plastic. Soon cars had soybean plastic gearshift knobs, light switches and horn buttons. Ford claimed that every car contained a bushel of soybeans. But Henry wanted a car that was all soybeans. To do this he had to make large plastic panels, which took longer to perfect. The first panels cracked. But eventually Henry had a plastic trunk lid attached to his car so he could show people how sturdy it was. He even hit it with an ax and didn’t make a dent. Henry affixed fourteen plastic panels to a steel frame, and showed off his new car on August 13, 1941. Unfortunately the car was never manufactured. Four months later America entered World War II. The soybean plastic car rolled into storage, its steel frame recycled in the war effort. Henry died shortly after the war, and no one continued his work on the plastic car. But his soybean research did spark a movement to use soy in manufacturing, which made soybeans the second largest crop grown in America. Furniture, flooring, candy, crayons, and all kinds of food contain soy. And even though we don’t drive soybean plastic cars yet, there are still plenty of beans in every Ford. All their seats are stuffed with soybean plastic foam. See Henry’s car here.  Henry Ford (July 30, 1863 – April 7, 1947) was an American captain of industry and a business magnate, the founder of the Ford Motor Company, and the sponsor of the development of the assembly line technique of mass production. By Hartsook, photographer via Wikimedia Commons  The world's first car made of what was called agricultral plastic is shown in February 1942. The plastic was a strong material combining soy beans, wheat and corn. Although the car never caught on, it was lighter and therefore more fuel efficient than the standard metal body. Wikimedia Commons  Despite the practical benefits of a car made out of food products (fuel efficiency and the conservation of steel that was scarce during World War II), the idea was the source of a lot of good-natured humor. From the Collections of The Henry Ford  Peggy Thomas is the author of such award-winning titles as Farmer George Plants a Nation, and For the Birds, the life of Roger Tory Peterson. Her newest book is Full of Beans: The Story of How Henry Ford Grew a Car, illustrated by Edwin Fotheringham. Vicki Cobb reviewed it. For more information about Peggy, check out her website: www.peggythomaswrites.com |
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For Vicki Cobb's BLOG (nonfiction book reviews, info on education, more), click here: Vicki's Blog *NEWSFLASH *
The NCSS-CBC Notable Social Studies Committee is pleased to inform you that 30 People Who Changed the World has been selected for Notable Social Studies Trade Books for Young People 2018, a cooperative project of the National Council for the Social Studies (NCSS) & the Children’s Book Council Categories
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