Volume and Mass

Today we practiced finding the mass and volume of different objects. First I asked the students to come up with some way to organize their information in their journals. Most eventually ended up with a table. To find the volume, we measured the water displacement after the object was placed in a graduated cylinder of 200 mL of water. To measure the mass, we used a triple beam balance. The most challenging object with regards to mass was the ball, which wouldn't stop rolling off the triple beam balance. Eventually the students realized they would need something to hold it. They chose a beaker, and figured out how to measure the mass of the ball without including the mass of the beaker - measure the mass of the beaker separately, measure the mass of the beaker and ball together, then subtract the mass of the beaker. 

Glow Stick Investigation

Glow stick dipped in hot water

Glow stick dipped in hot water

Glow stick dipped in hot water, then again in cold water at the bottom. You can see the difference!

We continued our discussion of the behavior of atoms this week with a glow stick investigation. We activated our glow sticks by popping them, making the liquids inside interact to cause the glow. Then we dipped the glow stick in hot water, and it immediately got much brighter. We discussed the reason for this was because those atoms are getting more and more energized by the thermal energy, so the chemical reaction causing the glow was happening faster. When we dipped the glow stick in the cold water, the color immediately dulled due to the loss of energy. The atoms began to slow down. Fun activity!

Subtraction Strategies

I began our exploration of subtraction strategies just as I did for addition strategies. I gave all the students the same subtraction problem, and let them solve the problem however they wanted. I selected several students to write their strategies on the board. Just as with addition, the kiddos were shocked at how many different ways their friends solved the same problem! We focused on two different strategies for subtraction: Number Line (which can look three different ways) and Subtracting by Place Value.

Particles in Different States of Matter

Our particles made out of stickers

We've been discussing ways to classify matter, and one way is by states of matter. By the time I get 4th graders, they've had lots of exposure to solids, liquids, and gases. Determining the state of matter for an object is nothing new. It's my job to introduce how heat can affect a state of matter, and what happens to the particles as the state changes.

We began by marking off a "jar" on the floor. We just used chairs as our boundaries. We packed ourselves into the "jar" and pretended to be the particles of a solid block of ice, frozen in a jar in the freezer. We were all touching, and no one was really moving much. Then we pretended someone took us out of the freezer and sat us down on the counter of a comfortably-warm room, so we started to slowly melt into a liquid. We began to move around and bump into each other, still within our jar. Finally, someone held us over the stove, so we began to move faster and faster, bumping into each other and the walls of the jar, until finally we became a gas and came out of the jar and flew around the room. We compared the particles of a gas to a sugared-up toddler. Ha ha!! Then we went in reverse and eventually became a liquid, then a solid again.

The Scientific Method

The last two days of science class have been all about the scientific method. We decided to do an experiment to determine what effects different liquids would have on the physical properties of gummy bears. We used a glass of water as our control, then brought in a glass of vinegar, a glass of water/baking soda, and a glass of water/salt. Before we put the gummy bears in the solutions, we first measured their length, width, thickness, and mass. We also observed their physical traits. Then we added the gummy bears to the solutions and left them overnight. The next day we observed their physical traits and again measured their length, width, and thickness. I hadn't ever done this experiment before, so I was pretty surprised by the differences we saw!!

Our gummy bears in relation to the normal one in front

Measuring the gummy bear left in salt

Tools Search

A student example of our journal entry

A student example of our journal entry

In science this week we did some research on our Mac Books. The students were challenged to find a picture of these different tools, then write the name and describe their use(s). I thought this might be more fun and meaningful than me showing them the tools and telling them the information. I had lots of great-looking journals!