## Simple Conservation of Mass Activity

October 5, 2010

by: Lee Walker

When we are doing a Partnership for Learning.com Science Adventure on phases of matter we like having this conservation of mass experience in the bag of tricks. It can be done in minutes and is extremely reliable. All you need is the simplest (and least expensive) OHAUS classroom balance from Educational Innovations, the Ice Melting Block set from Educational Innovations, a pair of wire cutters and some paper clips, (just in case you need to whip up some mass bits of less than a gram) and a nicely formed ice cube. We like to use the aluminum blocks and O-rings from two of the Ice Melting Block sets just to simplify the balancing and have found that having more than one set of the blocks is good for the original activity anyway.

Here we go…….

Step 1)

Place the materials  on a level surface with the balance set.

Materials:

A)  Set of brass weights

B)  2 or three paper clips and wire snips

C)  Classroom balance

D)  Aluminum Ice Melting Blocks and rubber O-rings

E)  Ice cube on a dish (actually, a Styrofoam meat tray is better than a saucer as it is very non-conductive, and the ice cube retains its temperature even better than on a ceramic surface.

Step 2)

Place the ice cube in the tray on the right, add necessary weights to achieve balance,

……………………………….AND WATCH WHAT HAPPENS

As the ice cube melts and water collects inside of the O-ring the balance is retained!

Step 3) Note that the ice cube is completely melted… (Actually long before the time indicated by the watch)… and the balance is right on the mark! No gain or loss. Only the form of matter has changed. All of the matter is still accounted for.

The Ice Melting Blocks allow this to be done without having to be concerned with evaporation OR loss of student interest. Lots of good data can be gathered, the phenomena discussed and conclusions drawn.

There you have another case where the Walker brothers rely on Educational Innovations and Jim Housley’s wonderful inventions!

February 26, 2009

by: Dave Crowther

Recently, I was asked to visit a first grade classroom and teach a lesson on Solids and Liquids. As a university professor, I always get excited when I get to work with real kids in real classrooms – there is nothing like the passion that children have when they are actively engaged in doing science! So, after looking up the specific standards and objectives as well as perusing through the adopted curriculum for the school, I chose to explore ice melting as an introduction to the lesson (engagement), making ice cream in a bag (exploration), and then making Gak (white school glue, water and Borax) as both the elaboration and assessment.

Having taught elementary school as well as teaching science methods for over 15 years, I know, as well as all of you know, the importance of having a good plan and being as organized with materials as possible. This organization even goes to the extent of pre-measuring glue into individual 2 ounce portion cups and mixing up the Borax to the specified solution ratio and then putting all of this into plastic bins so that I could easily hand a bin with the materials to each group.

I was ready to go. I showed up at the school thirty minutes early with 2 copy paper boxes loaded up with materials, only to find out that our lesson would be delayed another thirty minutes due to an assembly. Not a problem, I had the classroom to myself and quickly organized the materials and was ready to go when the kids entered the classroom. Oh, the energy these wonderful children have! We quickly got out the science notebooks that are used in the classroom and we drew pictures of the ice cube as it melted for the first two minutes (about the entire attention span of all of these children.) Then we decided to see what we could do to melt the cube faster and the creativity kicked in.

We had a brief discussion and introduced the words “Liquid” and “Solid” on the Science Word Wall. The kids constructed their own definitions and recorded them in their notebooks. We then went on to see if we could change a liquid to a solid by shaking ice cream in a bag surrounded by a larger bag with ice and salt. The kids ate their ice cream with much enthusiasm as we discussed properties of liquids and solids and added observations to the white board and refined our definitions on the word wall. The final stage of the lesson was to make Gak and then have the kids draw and label, or communicate as well as they could in their science notebooks, the properties of solids and/or liquids that the gak had when they played with it. Entries included ideas from our discussion and represented (for the most part) the definitions of solids and liquids that were observable in the gak. A great 60 minutes of science!

Now that you have read my experience teaching first graders science, I know that many of you have thoughts and ideas of how you teach this particular objective / standard. The reason for this blog is really two fold: 1) to provide a space for teachers to share lesson ideas and get lesson ideas for teaching science in the classroom. 2) To provide a space to have discussions of the content and materials that are required to teach science, along with some of the misconceptions that may be present.

As a teacher-friendly company, Educational Innovations is dedicated to helping all teachers get the information, materials and support that is needed for all children to experience science and become more science minded. Please share your thoughts and ideas within the blog and help us build this great resource.