More Than Just the Telephone: The Impact of Alexander Graham Bell

Unbeknownst to many, Alexander Graham Bell made outstanding contributions to aviation through his development of tetrahedral kites, the investigation of their application to personnel carrying aircraft, and his enlistment of talented associates who aided significantly in the progress toward accomplishing powered flight.

Expanding upon the design of the rectangular-celled box kite that Hargrave of Australia invented, Dr. Bell developed a three-sided triangular form of cell which he adapted to various multi-cellular shapes. This research led to a large kite in which on December 6th, 1907, his associate, Lt. Thomas Selfridge, flew to a height of over 160 feet.

Science Milestones: Alexander Graham Bell @EvaVarga.netAlthough his greatest scientific accomplishment was the invention of the telephone, Dr. Bell deserves wide recognition for his promotion of aeronautics. He was a member the Aerial Experiment Association that formed in 1907 who conducted flight experiments from his summer home at Baddeck, Nova Scotia.

“I have no doubt that a machine will be driven from the Earth’s surface at enormous velocities by a new method of propulsion – think of tremendous energies locked up in explosives – what if we could utilize these in projectile flight!” ~ Alexander Graham Bell

Believing that the substitution of an engine and propeller attached to the kite might permit free man-carrying flight, dispensing with the tethering line, Dr. Bell and Lt. Selfridge secured the services of Glenn H. Curtiss. Curtiss helped them to construct a proper engine, and they also engaged the assistance of J. A. D. McCurdy and F. W. Baldwin. These five men formed the Aerial Experiment Association for the stated purpose of “getting into the air” – which also put them in direct competition with the Wright brothers.


Science Milestones: Alexander Graham Bell @EvaVarga.netAlexander Graham Bell was born on March 3, 1847 in Edinburgh, Scotland. His mother was the daughter of a Royal Navy surgeon and was a skilled musician and portrait painter whose hearing loss when Bell was just twelve years old, brought deafness close to him.

Bell’s father, Alexander Melville, was the world world-famous inventor of “Visible Speech”, a code of symbols to guide the action of the throat, tongue and lips in the shaping of various sounds. It was devised as a key to the pronunciation of the words in all languages, but had become of most use in teaching the deaf to speak. His grandfather, Alexander, was a specialist in the correction of speech defects as well as a renowned public speaker, giving public readings from Shakespeare’s plays on London’s stages.

“Don’t keep forever on the public road, going only where others have gone. Leave the beaten track occasionally and dive into the woods.” ~ Alexander Graham Bell

Bell had natural musical ability and turned toward a career as a pianist. By the time he was 25, he was assisting his father at Weston House, a boys’ school near Edinburgh, and trading music and elocution lessons for instruction in other subjects. He continued his formal education at the University of Edinburgh and later specialized in the anatomy of the vocal apparatus at University College in London. At 22, with his formal education behind him, he became a partner with his father.

He moved with family to Ontario in 1870 and a year later Sarah Fuller, the principal of a school for the deaf in Boston, asked him to teach her teachers. His success lead to a professor appointment at Boston University.

Bell’s patent for his telephone was filed just two hours before another experimenter, Elisha Gray, filed his claim in the U.S. Patent Office.

While in Boston, Bell met the two men who financed his pioneer work with the telephone. Thereafter, Bell spent the latter part of his life in Washington, D.C. and his summer home in Nova Scotia. He became a United State citizen in 1882.

He died on August 2, 1922 at which time 14,347,000 telephone were in operation across the country.

Bring it Home

➤ Research and discuss the invention of the telephone, its origin, its innovations, its advantages and disadvantages, and how it has shaped today’s society.

➤ Watch a video about Alexander Graham Bell.

➤ Create a poster to illustrate the changes the telephone has undergone since Bell’s original invention.

Build a tetrahedral kite of your own. Test the flight and refine your design to make improvements.

➤ Research his contemporaries (Glenn Curtiss, the Wright brothers, Thomas Edison, etc.) and put together a presentation (PowerPoint, brochure, poster, video, etc.) to share with others their impact on technology.

➤ Although Bell is best known for inventing the telephone, he invented many other things. He held patents for 18 other inventions on his own and 12 for which he collaborated with others. Learn more about each of these.

Science Milestones

Visit my Science Milestones page to learn more about scientists whose discoveries and advancements have made a significant difference in our lives or who have advanced our understanding of the world around us.

Interested in learning about others who were born in the month of January? Hop over to Birthday Lessons in March to read posts by other iHomeschool Network bloggers.

Science Milestones: A New Astronomy with Johannes Kepler

Each month, I like to share a post celebrating the accomplishments of a scientist whose discoveries and advancements have made a significant difference in our lives. To honor the work of these amazing people, I provide a little peak into their life and share an unschool-style learning guides or unit study to guide you and your children on a path of discovery.

This month, I chose to honor the Johannes Kepler, who lived in an era when there was no clear distinction between astronomy and astrology. There was, however, a strong division between astronomy (a branch of mathematics within the liberal arts) and physics (a branch of natural philosophy).

Science Milestones: A New Astronomy with Johannes Kepler @EvaVarga.netJohannes Kepler

In 1596, the German astronomer published his first important work on astronomy, Mysterium Cosmographicum (The Cosmographic Mystery). As well as defending the heliocentric model of the universe previously proposed by Copernicus in 1543.

Kepler explained the orbits of the known planets around the Sun in geometric terms in an attempt to unravel “God’s mysterious plan of the universe.” To do this, he dow upon the classical notion of the “harmony of the spheres” which he linked to the five Platonic solids – octahedron, icosahedron, dodecahedron, tetrahedron, and cube.

Science Milestones: A New Astronomy with Johannes Kepler

The Platonic solids, when inscribed in spheres and nested inside one another in order, correspond to the orbits of the planets Mercury, Venus, Earth, Mars, Jupiter, and Saturn.

In 1619, he published Harmonices Mundi (The Harmony of the World) wherein he stated his third law of planetary motion. He described the relationship between a planet’s distance from the Sun and the time taken to orbit around it as well as the speed of the planet at any time in that orbit.


Science Milestones: Johannes KeplerKepler was born in the small town of Weil der Stadt in the Swabia region of Germany and moved to nearby Leonberg with his parents in 1576. His father was a mercenary soldier and his mother, the daughter of an innkeeper. Johannes was their first child.

When Johannes was just five, his father left home for the last time and is believed to have died in the war in the Netherlands. As a child, Kepler lived with his mother in his grandfather’s inn. He tells us that he used to help by serving in the inn.

Kepler’s early education was in a local school and then at a nearby seminary. Intending to be ordained he went on to enroll at the University of Tübingen, a bastion of Lutheran orthodoxy.

Throughout his life, Kepler was a profoundly religious man. All his writings contain numerous references to God, and he saw his work as a fulfilment of his Christian duty to understand the works of God.

At Tübingen Kepler was taught astronomy by one of the leading astronomers of the day, Michael Mästlin. The curriculum was of course, geocentric astronomy, in which all seven planets – Moon, Mercury, Venus, Sun, Mars, Jupiter and Saturn – moved around the Earth, their positions against the fixed stars being calculated by combining circular motions.

This system was more or less in accord with current Aristotelian notions of physics, though there were certain difficulties. However, it seems that on the whole astronomers were content to carry on calculating positions of planets and leave it to natural philosophers to worry about whether the mathematical models corresponded to physical mechanisms. Kepler did not take this attitude. His earliest published work, Mysterium Cosmographicum, proposed to consider the actual paths of the planets, not the circles used to construct them.

 “I am satisfied…to guard the gates of the temple in which Copernicus makes sacrifices at the high altar.” ~ Johannes Kepler

Kepler was one of the few pupils to whom Mästlin chose to teach more advanced astronomy by introducing them to the new, heliocentric cosmological system of Copernicus. Kepler seems to have accepted almost instantly that the Copernican system was physically true.

Soon after moving to Regensburg in 1630, he became seriously ill with fever and on November 15 he died.

Bring it Home

What are Kepler’s three laws of planetary motion? How were his ideas viewed by his contemporaries?

Learn more about star polyhedra, discovered by Kepler in 1619 and prominently featured in the architecture of European churches.

Build models of the five Platonic solids; consider The Finnish Craft of Himmeli or Paper Models of Polyhedra.

Research the epitaph inscribed on his gravestone (sadly swept away in the Thirty Years War):

I used to measure the heavens,
now I shall measure the shadows of the earth.
Although my soul was from heaven,
the shadow of my body lies here.


Science Milestones

Visit my Science Milestones page to learn more about scientists whose discoveries and advancements have made a significant difference in our lives or who have advanced our understanding of the world around us.

Interested in learning about others who were born in the month of January? Hop over to Birthday Lessons in December to read posts by other iHomeschool Network bloggers.

The Engineering Feats of Alexandre-Gustave Eiffel


Each month, I like to share a post celebrating the accomplishments of a scientist whose discoveries and advancements have made a significant difference in our lives. To honor the work of these amazing people, I provide a little peak into their life and share an unschool-style learning guides or unit study to guide you and your children on a path of discovery.

This month, I chose to honor the Alexandre-Gustave Eiffel who is most recognized for creating the Eiffel Tower.

Science Milestones: The Engineering Feats of Alexandre-Gustave Eiffel @EvaVarga.netAlexandre-Gustave Eiffel

When the Statue of Liberty’s initial internal designer, Eugene Viollet-le-Duc, unexpectedly passed away in 1879, the Franco American Union and Auguste Bartholdi (the French sculptor who designed Lady Liberty) hired Alexandre-Gustave Eiffel as his replacement.

While Eiffel praised and retained Viollet-le-Duc’s plans for the sculpting and connection of the copper sheets (he would use Viollet-le-Duc’s repoussé technique and armature bars), he ultimately changed the initial plans for the interior design in favor of a modern approach. The Statue’s new internal structure would not rely on weight to support the copper skin but rather a flexible, skeletal system.

Eiffel designed a tall, central pylon (92 feet, or 28 meters) to be the primary support structure of the Statue’s interior. The pylon serves as the central attachment point for a lightweight truss work of complex asymmetrical girders which forms the Statue’s body. To connect the Statue’s copper skin to the pylon, flat metal bars are bolted at one end to the pylon and to the copper skin at the other end.

While the bars hold the Statue together, they also create flexible suspension (due to their malleability), acting like springs allowing the Statue to adjust and settle into the environment. This elasticity of Eiffel’s design is important because the Statue has to withstand winds from New York Harbor, temperature changes, and various other weather conditions.

Once his plans were approved, Eiffel supervised the Statue’s internal construction until its completion in late 1883. A few years later, Eiffel began his most famous project: the Eiffel Tower, which was completed for the Universal Exposition of 1889 (Exposition Universelle de 1889) in Paris. Eiffel died on December 27, 1923 in Paris, France.


A prominent French architect and structural engineer, Alexandre-Gustave Eiffel was born on December 15, 1832 in Dijon, France. Interested in construction at an early age, he attended the École Polytechnique and later the École Centrale des Arts et Manufactures (College of Art and Manufacturing) in Paris, graduating in 1855. Setting out on his career, Eiffel specialized in metal construction, most notably bridges. He worked on several over the next fewdecades, letting mathematics find ways to build lighter, stronger structures.

Science Milestones: EiffelIn his early work designing railway bridges, Eiffel relied on sophisticated mathematical designs renowned for their lightness, grace, and strength.

Eiffel is most famous for what would become known as the Eiffel Tower, which was begun in 1887 for the 1889 Universal Exposition in Paris. The tower is composed of 12,000 different components and 2,500,000 rivets, all designed and assembled to handle wind pressure.

The structure is a marvel in material economy, which Eiffel perfected in his years of building bridges—if it were melted down, the tower’s metal would only fill up its base about two and a half inches deep.

In his final years, Eiffel turned his interest to meteorology. He continued to study the subject at length until his death on December 27, 1923.

Bring it Home

There are a variety of ways in which you can expand upon your study of Eiffel. Consider some of the following suggestions to get you started.

🗼Learn more about his earlier engineering projects, including the Eiffel Tower in Paris.

🗽Explore the science behind the Statue of Liberty, Visiting the Statue of Liberty & Chemical Reactions.

Science Milestones

Visit my Science Milestones page to learn more about scientists whose discoveries and advancements have made a significant difference in our lives or who have advanced our understanding of the world around us.

Interested in learning about others who were born in the month of January? Hop over to Birthday Lessons in December to read posts by other iHomeschool Network bloggers.


Meet the Women in Science with a New Card Game

As a naturalist, the history of science has always fascinated me. I recall fondly reading about the impact Linnaeus had on scientific classification in my college biology classes. I was spellbound as I discovered how Rachel Carson sparked the environmental movement with the publication of her book, The Silent Killer. Many homeschoolers are familiar with naturalist and educator, Anna Botsford Comstock, author of The Handbook of Nature Study.

women in science

I received this game in exchange for an honest review; please see my disclosure policy for details.

History of Science

For the past couple of years, I have been writing a series of Science Milestones posts to celebrate the scientists whose discoveries and advancements have made a significant difference in our lives. I have enjoyed sharing short biographies of the people who have advanced our understanding of the world around us.

In addition to the short biographical sketch, I share a list of lesson ideas and activities teachers and students can use to further explore the science these remarkable scientists have made.  I have come to realize, however, that though female scientists do exist, they have rarely received the recognition they deserve.

Women in Science card game

I recently discovered a innovative card game designed specifically for young people to learn about Women in Science. The fundamental idea of the game is to familiarize players with women who have left their mark on science. Often, these women in science did not receive the recognition they were due.

Women in Space

Photo courtesy of / Francis Collie

As stated by the game creators, Anouk Charles & Benoit Fries,

It’s hardly surprising that few girls display an interest in physics or mathematics when they never hear about women who made extraordinary discoveries in these spheres.

The game is composed of 54 beautiful cards in a full color tuck-box. What I love best about these cards is the versatility. You can play the original, strategic game based on the card colors, collect the cards much like baseball or hockey cards, or play any standard card game requiring 52-cards using the logo in the top left corner of each card. Not only that, but you can also play an online version of the game.

Women in Space

Photo courtesy of / Francis Collie

The original Women in Science 54-card set retails for $12 and the new Women in Space expansion set retails for $8. The cards are available in both English and French. A free printable PDF is available in Spanish. What is not to love?

Carl & Gerty Cori Change the Face of Medicine

In brilliant collaboration, Carl and Gerty Cori studied how the body metabolizes glucose and advanced the understanding of how the body produces and stores energy. Their findings were particularly useful in the development of treatments for diabetes. They were awarded the Noble Prize for their discovery of how glycogen (animal starch) – a derivative of glucose – is broken down and resynthesized in the body, for use as a store and source of energy.

cori cycleThe pair were interested in how the body utilizes energy. The couple spent more than three decades exploring how the human body metabolizes glucose. It was known in the 1920s that faulty sugar metabolism could lead to diabetes, and it was also known that insulin kept the disease in check.

The effect of insulin on blood sugar levels had been observed, but scientists did not understand the biochemical mechanism behind insulin’s effect or how carbohydrates were metabolized. In 1929, the couple described what is now known as the Cori cycle; an important part of metabolism. To put it simply, lactic acid forms when we use our muscles, which is then converted into glycogen in the liver. Glycogen, in turn, is converted into glucose, which is absorbed by muscle cells.

The Cori Cycle

cori cycleThe Cori Cycle refers to the metabolic pathway in which lactate produced by anaerobic glycolysis in the muscles moves via the blood stream to the liver where it it is converted to blood glucose and glycogen. High intensity exercise will mostly get it’s energy or ATP from the pathway of the glycolitic system.  Less intense activity will receive its energy or ATP from the aerobic pathway utilizing the Krebs cycle.

When utilizing the glycolitic system, cycle after cycle, lactate will start to build up.  Lactate from the glycolitic system will diffuse from the muscles into the bloodstream.  It will then be transported into the liver.  In the liver it is converted from lactate back to pyruvate back to glucose, which is then available to the muscles again for energy, this is called gluconeogenesis.  The whole process is called the Cori Cycle.

The more you train with high intensity exercise, the more capable the enzymes and transporters become that are needed for the Cori Cycle.  Your liver gets better at using the lactate, not more efficient (it still needs the same amount of ATP to run the Cori Cycle) but it will do the cycle faster.

Gerty Cori Biography

carl & gerty cori Gerty Radnitz was born in Prague in what was then Austria-Hungary. She received her PhD in medicine from the German University of Prague’s Medical School in 1920. It was here that she met fellow classmate, Carl Ferdinand Cori, whom she married later that same year.

The couple moved to Buffalo, New York in 1922 and began researching metabolic mechanisms. As a woman, Gerty Cori was employed on much less favorable terms than her husband and encountered other forms of gender discrimination throughout her career.

The couple moved to Washington University in St. Louis in 1931 after both were offered positions there. When the Coris were hired at Washington University, she received one-tenth Carl’s salary, even though they were equal partners in the laboratory.

Gerty and her husband continued to investigate how glycogen is broken down into glucose and in 1939 were able to both identify the enzyme that initiates the decomposition and also to use the process to create glycogen in a test tube.

She became full professor in 1947, the same year that she and Carl were awarded the Nobel Prize “for their discovery of the course of the catalytic conversion of glycogen.” She was the first American woman to win the Nobel Prize in Science.

Around this time Gerty was diagnosed with myelosclerosis, a disease of the bone marrow. She died in 1957 at the age of 61.

Bring it Home

Try this hands-on lab from Amy Brown Science to discover The Use of Glucose in Cellular Respiration

Enjoy the Carl and Gerty Cori and Carbohydrate Metabolism commemorative booklet produced by the National Historic Chemical Landmarks program of the American Chemical Society in 2004.

Read about the dip-and-read test strips developed by Helen Free and her husband, Al. Originally designed to test for glucose in urine, the test strips were such an advance that researchers have since combined 10 urine tests to check for ailments like liver failure, urinary tract infections, and others—onto one plastic stick.

Learn more about our digestive system with these hands-on enzyme labs.

Investigate What Types of Food Contain Starch and Protein?

Building Macromolecule is a paper-scissors-tape activity used to help students envision the process of synthesis, building macromolecules out of smaller subunits.

Science Milestones

Visit my Science Milestones page to learn more about scientists whose discoveries and advancements have made a significant difference in our lives or who have advanced our understanding of the world around us.

Interested in learning about others who were born in the month of August? Hop over to Birthday Lessons in August to read posts by other iHomeschool Network bloggers.


Rosalind Franklin: The Unsung Hero of DNA Structure

Rosalind Franklin, a scientist whose role in the discovery of DNA structure in 1953 has been forgotten by many, has a chance to be immortalized in a feature film. Throughout her career she faced sexism at nearly every turn. She also happened to be Jewish, which heightened the prejudice against her. Her name may soon be on the tips of everyone’s tongue and her role in the discovery of DNA Structure known to all. Entertainment One has acquired the script to Exposure, her life story.

In 1962 James Watson, Francis Crick, and Maurice Wilkins jointly received the Nobel Prize in physiology or medicine for their 1953 determination of the structure of deoxyribonucleic acid (DNA). Rosalind Franklin (1920–1958), a colleague of Wilkins, died of cancer at the age of 37, and was thereby not equally honored because the Nobel Prize can only be shared by three scientists. It was her work in X-ray crystallography, however, that proved critical to the correct solution to DNA structure.

Unsung Hero of DNA Structure @EvaVarga.netWhat is DNA?  

DNA is the material embedded in the cells of all living organisms that carries the genetic coding that determines how a living thing will look and function. It is found in the nucleus of each cell and is unique to every individual – whether human, mountain lion, or butterfly. Its full name is deoxyribonucleic acid, which can be complicated to say, so we usually refer to it as DNA for short.

DNA is so tiny that it can not be seen unless we use a very powerful microscope. If we could see it we would see that it looks like a twisted ladder, which scientist refer to as the double helix. Each rung or step on the DNA ladder is composed of two letters.

There are only 4 letters — A,T,G, and C — and each has a unique puzzle-like shape. This means that A and T fit together to form a rung on the ladder and G and C fit together to form another rung on the ladder.

As we read the DNA ladder, the letters combine to form 3-letter words called codons. Then, these codons combine to form sentences that we call genes. These genes are the basis for your chromosomes, which give your body a blueprint or set of instructions for life.

Every human has 23 pairs of these DNA chromosomes that determine what we look like and how to perform. We get one set of chromosomes from our mother and one set from our father. Our chromosomes determine whether our eyes will be blue or brown, what color our skin and hair will be, whether we will be a boy or girl and so much more.

The Structure of DNA

Building a Cardboard Safari DNA Double Helix Puzzle

Discovering DNA Structure

Inspired by Linus Pauling’s success in working with molecular models, James Watson and Francis Crick rapidly put together several models of DNA and attempted to incorporate all the evidence they could gather. Franklin’s excellent X-ray photographs, to which they had gained access without her permission, were critical to the correct solution. Along with Wilkins, Franklin’s partner, the four scientists announced the structure of DNA in articles that appeared together in the same issue of Nature.

After the publication, they moved on to different projects. Franklin went to Birkbeck College, London. Before her untimely death from cancer, she made important contributions to the X-ray crystallographic analysis of the structure of the tobacco mosaic virus, a landmark in the field. By the end of her life, she had become friends with Francis Crick and his wife and had moved her laboratory to Cambridge, where she undertook work on the poliovirus.


Rosalind Franklin @EvaVarga.netRosalind Franklin was born July 25, 1920 to a Jewish family in London, England. Educated at private schools in London, she studied natural sciences at Newnham College, Cambridge, from where she graduated in 1941. She joined the University of Cambridge where she earned a research fellowship in a physical chemistry laboratory under Ronald George Wreyford Norrish. The British Coal Utilisation Research Association offered her a research position in 1942, and started her work on coals. This helped her earn a PhD in 1945.

In 1947, she went to Paris as a chercheur (post-doctoral researcher) under Jacques Mering at the Laboratoire Central des Services Chimiques de l’Etat, where she became an accomplished X-ray crystallographer. She returned to London in 1951 and became a research associate at King’s College. She was compelled to move to Birkbeck College after two years, however, owing to disagreeable clashes with her director and more so with her colleague Maurice Wilkins. At Birkbeck, J. D. Bernal, chair of the physics department, offered her a separate research team. She died on April 16, 1958 at the age of 37 of ovarian cancer.

Bring it Home

Build a model of the DNA Double Helix with the Cardboard Safari Puzzle

Create a model of DNA with colorful Wiki-Sticks

Extract DNA from Strawberries in this great lab from Marci at the Homeschool Scientist

Explore the DNA Teaching Resources from Karyn at Teach Beside Me

Challenge your students with this Transcription / Translation Lab Activity 

Download the DNA & RNA Protein Synthesis Interactive Notebook Resources from Science with Amy

Make these cool DNA Sequence Bracelets

Watch this fabulous NOVA documentary on PBS, The Secret of Photo 51

Science Milestones