Students will need just one color pencil for this line graph.  Red is a good choice.  Point out to students that each of the small marks represents 100, so the first dot they place will be close to the zero.  After students place small dots for the data, have them connect the dots with straight lines.

What the Chart Shows

   This chart shows that in the early 1800s, a very significant change was underway in the United States.  As the Industrial Revolution began, inventors saw the opportunity to profit by developing ideas and applying for patents.  There are ups and downs in the early decades due to various factors, but clearly the trend is upward.  Around 1850 the number of patents issued is soaring. 
   An important point to make is that this inventiveness was promoted and supported by the patent system, which protects the inventor's right to profit from his or her invention.  Without that protection, few people will spend the countless hours of work and frustration that is usually a big part of the inventor's life.
 
 

   Students will need just one color pencil for this bar graph.  Green is a good choice.  Notice that the numbers in the table must be converted to millions.  The first figure, 73,000, is equal to less than one tenth of one million.  So the first bar will be very short.  (Each small mark represents one tenth million, or 100,000.)
   The second bar will also be fairly short, since the figure for 1820 is 0.335 million.

What the Chart Shows

   This chart shows rapid growth of the cotton crop in the United States in the decades leading up to the Civil War.  Cotton was not widely grown before 1800, because the seeds are difficult to get out of the raw cotton by hand. 
   The invention of the cotton gin in 1793 by Eli Whitney changed the economics of cotton growing.  The new machine made it easy and cheap to remove the seeds.  Suddenly, the crop became very profitable, and was widely planted in the Southern states. 
   Students should also know that the spread of cotton growing tended to increase the demand for slavery.
 
 

   "What decades seem to be..."

   One of the dramatic jumps on the graph is the period from 1820 to 1830.  The jump is probably related to the rise of the textile industry in the New England states.  This decade is often cited as evidence that the Industrial Revolution had taken hold in America.
   Another impressive jump comes in the decades of the 1840s and 1850s.  By that time the railroad industry was growing very rapidly, and factories of all kinds were being established.  Steam power was replacing water wheels.  All of these changes involve new ideas and new technology, and this is reflected in the patent figures.

   "How did the cotton crop..."

   The cotton crop tended to pull the North and South together because textile factories that began growing in the New England states needed the cotton grown in the South.  Cotton was cheaper than wool, and was easily adapted to the machine production of thread and cloth.  Many Northern factory owners realized that their financial interests were closely connected to the cotton crop grown in the South.
   But the cotton crop was also a force in the growing split between the North and South.  Cotton growers believed that slavery was essential to producing the crop.  Paid laborers might walk away at the critical harvest time, or hold out for exorbitant wages. 
   As the cotton crop grew larger and economically more important, plantation owners took a harder line on the slavery issue.  That was in contrast to many Northerners, who were increasingly speaking out against slavery.