Second graders are closing out the year making play-doh with the best properties--play-doh that's not too sticky or too gritty.  With all the suggested improvements, we came pretty close!

Students received their engineering notebooks back, and multiple recipes are included in their notebooks as the last entry!  Make some play-doh over the summer, and let me know how it turns out.  Did you improve the process we thought produced the best quality play-doh?  Or was the process we came up with the best?  Happy summer!

Second graders are connecting what they learned about rearranging pieces of matter to create a new object.  The same is true with our play-doh process.  In both processes, we used the same ingredients--flour, salt, and water.  How we arranged those ingredients affected the play-doh we got.  We'll close out the year making the best play-doh with the properties we desire--play-doh that is smooth and not too sticky!

One second grade class added salt, then water and then flour.
The other second grade class decided to make the water hot before adding it to the salt, and then added the flour.

Each play-doh was smoother and less sticky than the original process!  Each student has a copy in their notebooks.

So the second graders have created their tests...and now it's time to investigate the materials used to make play-doh!

The three ingredients we will be using to make play-doh are flour, salt, and water.  Students determined the properties of each material by observing them with their sense of sight and their sense of touch.  They also hypothesized what each material would do to the mixture.  

Second graders agreed that:
1.  Adding more salt would make the play-doh grittier, since it felt like sand.
2.  Adding more flour would make the play-doh drier and possibly softer since it didn't feel wet or hard.
3.  Adding more water would make the play-doh stickier because it was wet!

Now on to make some play-doh!

To close out our unit on matter, second graders will be investigating what happens when you mix solids and liquids together.  They'll be considering the properties of the solids and liquids before and after they are mixed in order to optimize a product they will be making...PLAY-DOH!

Students are first comparing high-quality play-doh to low-quality play-doh, recognizing the properties that make them such.  Our high-quality play-doh is store bought, while the low-quality play-doh is homemade. They'll be creating tests and gathering data to determine which mixture they design is most like the high-quality play-doh!  As engineers, they will be improving the process to make play-doh.  

Second graders are gathering evidence to show that matter can indeed change, just like their objects changed when the pieces where rearranged.  But can the pieces stay the same and just look different?

By building "snowmen" made of ice, second graders will make observations throughout the day to see how matter can change.  In this case, the water used to make the snowmen will undergo a physical change.  Each "snowball" began as liquid water in a balloon.  Put in the freezer, the water changed to ice.  Now out of the freezer, what will happen to them?  Only time will tell!

All matter is made up of small particles called atoms.  Atoms can be rearranged to make matter with different properties.  Second graders are digging into this concept by seeing how different objects can be made up of the same set of pieces.  These pieces can be broken apart and rearranged into something new.  We're using Legos to help us discover this!  

Check out these second graders' creations.  Notice how two students created different objects from the same set of Legos...

Soon we'll see how we can rearrange these pieces even more to get something totally new!