Sixth Graders Prepare for the Hour of Code

Sixth graders are working hard and long to prepare for the Hour of Code event planned for December 8th with the third graders at Marshall.   Teaching certificates are being earned by the sixth graders to show they are highly qualified to share what they know about the coding activities with their third grade partners.

Some sixth graders, including Elesia and Kyron have gone above and beyond earning certificates.  They have written code to create a program on "Scratch" that will play the song, Jingle Bells.  The girls used tuning forks to help them decide the notes that they should use and through trial and error have been able to complete the program.   All students are learning that programs and apps have human minds behind them that have spent hours coding each step of the programs that we enjoy using.  The computer  is capable of artificial intelligence or simulating human intelligence, but it takes a human brain to do the creating.
 
Why are we doing this?? According to Hadi Partovi from Code.org “Every student deserves the chance to learn computer science to access the best careers of the 21st century.”  

Grams/Volume=Density=STEM

While studying surface water, sixth graders learned that ice is less dense than water.   In an effort to understand exactly what this means, students completed a STEM activity where they determined the density of 12 materials ranging from different types of plastics, to wood and metals.

The Science and Math part of the activity was completed when students used balance scales and measuring tapes to find both the mass and volume of the objects. To determine density, they used math skills to complete the algorithm M/V=D.

In the Technology piece, students used Microsoft excel to complete a bar graph to display the differences in densities found and wrote statements of analysis.

Engineering uses the properties of materials to determine uses for the material.  Students were able to see that out of all the metals tested, (steel, copper, brass and aluminum,) aluminum had a density of 2.72 compared to the other metals with densities above 7.0.  This is why aluminum is used in making airplanes. 

Ice is one of the few solids that is actually less dense than the liquid form of the same substance.  The formation of ice on the surface of a lake or pond helps protect the organisms that live in the water from extreme winter temperatures.  Maybe God understands density better than the rest of us!

Population Changes in Surface Water

Sixth graders have been collecting water data both virtually and in real time as they compare the pond populations in EcoMUVE to specimens found in the outdoor classroom. 

One of the most serious causes of poor water quality in our county is eutrophication.  This is when nutrients flow into the water with sediment and cause algae growth.  Bacteria feed on the algae when it dies and deplete the water of oxygen.  Fish kills occur because of the lack of oxygen.

Students are working in small groups and using the data they have collected to create and analyze graphs that support the theories they have developed on why the fish are declining in population. 

The theories are not the same, but a lot of scientific reasoning is taking place while students try to prove their theory to their friends.  

 

Hypertonic to Hypotonic Flow - Osmosis! Let's Go!

Sixth graders have completed a lab on osmosis using gummy bears as a model of the cell.  The masses of three gummy bears were determined.  One was placed in an empty cup as a control.  One was placed in 250ml of water, and the final one was placed in 250ml of water in which a sugar cube had been added. 

Osmosis is the diffusion of water from an area of greater concentration to lesser concentration.   The bears that had been placed in sucrose water and tap water increased in mass after 72 hours by an average of 9 grams and 11 grams respectively.  The masses of the control bears stayed the same.

Students concluded that the bears were hypotonic to the water and therefore the water from the cup diffused through the outer membrane of the bears through osmosis into the gummy bear. 

Qualitative data was recorded as well.  Bears became soft, slimy and more fragile. 

Cellular Respiration

Transpiration of oxygen and water out of the stomata of leaves was evident in the plants found in the outdoor classroom this week.  Sixth graders placed a plastic bag around a leaf and left it for 24 hours.  When they returned to check on the project, most students found between 2.5 and 5 ml of water in their bag. This process proved that cellular respiration had taken place in the cells of the chosen plant.  

In cellular respiration, the mitochondria in cells convert small glucose molecules into energy, carbon dioxide, and water. This process is the other half of the energy cycle. Photosynthesis and cellular respiration are the two processes in the energy cycle. 

Students also completed a chromatography investigation where they took leaves from some of the green plants and placed them in alcohol.  After allowing the chlorophyll to break down, they placed a filter into the solution to separate the chlorophyll from the other colors in the leaf.  The fall leaf colors have been in the leaves throughout the growing season, we have not been able to see them because of the chlorophyll.  When plants start to go dormant for the winter, the chlorophyll breaks down and the other colors begin to show. 

Students were able to study the leaves at both the macro and micro scale by using the digital microscope with an ipad. 

How Do Cells Function?

How do you explain the ways cells contribute to the function of living organisms?  In an effort to promote the basic understanding of the role of cells in body systems and how those systems work to support the life functions of the organism, students have been completing experiments and modeling the cell organelle functions. 

Students placed raw eggs into five different solutions to see if the solution would pass through the barrier of the shells to affect the circumference of the egg.  Both quantitative and qualitative data were taken over a five day period to record changes in the egg.  Students inferred that the process of osmosis allowed some of the substances to pass through the shell and increase the size of the egg.   Students included a control egg that was not placed into any solution.  This was offered as evidence that it was the solutions that were affecting the egg size.  Constant variables that should stay the same were also identified to make sure that the experiment was a fair test.

Students then moved to the outdoor classroom to make cell models out of materials found outside.  The cell membrane was represented with a plastic bag and the cytoplasm that the materials were placed into was made of corn syrup.  Students then explained which biotic factors they chose to represent the organelles and why they were chosen.

Life Comes From Life!

Sixth graders have been studying cells and cell theory in Science.  They have created models, group diagrams, and microscope slides of real specimens from the outdoor classroom wetland.

The conclusions they have drawn support the cell theory.

All organisms are made up of cells.  Some are multicellular and some are unicellular. The cells allow the organisms to carry out the functions of life. All cells come from existing cells.

In Technology class, students are looking at the cells from the macro scale.  They are collaborating with google shared documents over the systems of the body and preparing presentations to share with classmates.