Filtering Fun!!

Time continues to rush by as we successfully complete our fifth science lesson!  This week, the students attempted to separate the water mixtures they made last week (gravel, tissue, salt).  Kathy started out this week with a great introduction that reviewed the science question and process skill of last week.  She also introduced the science question (Can all mixtures be separated using the same method?) and process skill (predicting) for this week.

Then we jumped into the writing assignment that asked the students to predict what will happen when we separate each mixture.  We had a section to write and a section to draw a picture as well.  Even after we explained the prompt and passed out the papers, we still had some confused looks.  So Kathy made a great move gave the students some additional guidance about using the numbers 1, 2, and 3 to organize their writing, and recalling the mixtures from last week.  We also reminded them that this was not a test, just a casual writing prompt.  After that, the students came up with some great predictions.  

Then, we changed gears and gathered the students on the rug to view the technology portion of our lesson, the song and video from They Might Be Giants Solids, Liquids, Gasses.  The students, mesmerized and laughing, LOVED the video!  And I couldn't get the song out of my head for the rest of the day!  They definitely enjoyed the technology, and now more than ever, it is important for teachers to bring technology into the classroom.  After explaining the steps for the day and the safety precautions, the students went back to their desks and observed the mixtures of last week to see how they have changed.  Kathy passed out the old mixtures and the chart that we created for the students to record their findings.  

Then Kathy led the students in a brainstorming session about how they could possibly separate their mixtures.  They came up with some great ideas, including a filter, which was a great connection to the rest of the lesson.  After putting filter on the science word wall and showing real life examples, the students began filtering their mixtures and trying to separate the solid from the water.  Since this lesson required so many materials, we decided to use groups of 4 and 5 students.  With the classroom set up and the nature of the lesson, this wasn't the best group structure.  Some students argued over taking turns and other's had difficulty seeing.  If we do this lesson again, we will probably use smaller groups.  With some of our much practiced classroom management, the students were still successful at grasping the main idea of the experiment.  They found that they could easily separate the gravel and the tissue with the filter, but not the salt.  

We then gathered the students on the rug again for the lesson conclusion.  Unfortunately, we are not going to be teaching long enough to do the lesson where the students evaporate the water to separate the salt.  We felt that this was too much of an important point to ignore or just gloss over.  So I did my own little experiment in my kitchen and boiled a salt water mixture to separate the salt from the water.  I recorded a short video of the experiment and took some pictures to show the kids.  I also brought in the pot that I used to show the students and they each got to touch the salt.  We were pressed for time during this lesson, and almost decided to wait to show the salt next week.  But as the lesson went on, we were able to fit it in.  They were very interested to see this, since most of them said they thought the salt was permanently in the water and could not be separated.  I definitely think it was worth it to actually show the students how the salt can be separated by evaporating the water.  Then I asked the students the science question again, and reviewed the process skill of prediction.  And just like that, another science lesson under our belt!!