On June 10, 1967, the Gateway Arch was opened to the public. Unit resources.
During a thunderstorm on September 3, 1970, hail formed, creating the heaviest hailstone of the 20th century. The hailstone fell on Coffeyville, Kansas. It weighed 1.67 pounds and had a circumference of 17.5 inches. That record has now been broken, although the Coffeyville hailstone still ranks among the world’s largest. What Causes Hail? Below an […]
Blaise Pascal was a scientist, mathematician, inventor, and theologian who was born on June 19, 1623. Unit resources.
Great Lakes unit study. On March 19, 1687, Robert La Salle died in Texas.
On September 13, 1994, President Bill Clinton signed the Federal Crime Bill, which included the U.S. DNA Identification Act. This act authorized the establishment of a national index to keep track of DNA samples taken from convicted criminals and to allow for the analysis of DNA samples from crime scenes and unidentified human remains. DNA […]
On May 24, 1844, the first Morse code telegraph message was sent. Samuel Morse unit resources.
One of our more popular units is on the Transcontinental Railroad. This May 10 is the 150th anniversary of the Golden Spike ceremony that was held to commemorate the completion of the railroad. What a great opportunity to learn more about the vast impacts of the Transcontinental Railroad along with trains in general, Westward Expansion, […]
Jules Verne was born on February 8, 1828, at a time and a place of rapid scientific developments. Unit resources.
The latest known inscription written in Egyptian hieroglyphs stands in the temple of the goddess Isis on an island in Lake Nasser. The date of this inscription, the Graffito of Esmet-Akhom, is August 24, 394. The Graffito of Esmet-Akhom was evidently written for the benefit of a few pagans in the Red Sea area and […]
On January 27, 1880, Thomas Edison patented the electric incandescent lamp. The incandescent light bulb was invented by Thomas Alva Edison in the year 1879. Despite the fact that it was invented over one hundred years ago, the principle behind the design is still the same today as it was then. How an Incandescent Light […]
Five minutes too late! Phileas Fogg was due back in London on December 21 and was to make his appearance at his usual club no later than 8:45 PM. Unit resources.
On December 6, 1947, President Harry Truman dedicated the Everglades National Park, recognized for its diversity of plants and animals.