## Friday, November 30, 2018

### Maths of Practical Life: Mass and Volume

A busy and exciting week as we dove deeper into the Metric System!

We looked at units of measurement for length (meter), mass (gram), and volume (liter). We practiced estimating in grams every day with the Estimation Wall. This is a fun activity to do at home, too, if you have a scale which can give you the mass of something in grams. I just used my little kitchen scale. Choose an item and let everyone guess its mass. When all of the guesses have been written down, weigh the item. Whoever had the closest guess is the winner. Write the item name and its mass on a sticky note and put it up on the wall. Leave the collection of sticky notes up, with a new item and a new sticky note being added each day, so that people can see this information and gradually increase the accuracy of their estimates.

Our items were

• Monday - chalkboard eraser (45 g)
• Tuesday - red onion (346 g)
• Thursday - poker chip (3 g)
• Friday - lemon (75 g)

Students found this activity to be quite fun... so much so that they've asked me to continue it over the next few weeks as part of our daily math.

In order to help us better understand meter, gram, and liter, we also made a recipe in metric every day this week. The recipes had to be nut-free, vegan, and quick enough to make with children in just an afternoon. Here they are:

All of these recipes were delicious and not very difficult!

On Monday we will add finishing touches to our main lesson books (numbering pages, adding the table of contents, decorating the front and back covers) and then it will be time to move on to our December topic, the Class Play. The Measurement Main Lesson Book is our first written in Script and includes two page spreads on clocks, calendars, reading a thermometer in Fahrenheit and Celsius, conductors and insulators, mass vs. weight and mass vs. volume, the Metric Stair, and our Estimation Wall activity results.

do we measure a solid, like an eraser, in mL or in grams?

I place the item under the arrow each day;
student estimates are written on the chalkboard itself

estimates for the mass of a red onion on Day Two

Monday, November 26

• continue calendar making project and make art and write in numbers for September 2019

• introduce and do the estimation wall activity: chalkboard eraser
• briefly explain the difference between mass, weight, and volume (note that weight can change based on gravity and volume can change based on temperature, but mass is a constant)
• do Exploring Heat 8 activity from NEED EnergyWorks student packet and create a line graph of our results (as a group)
• make metric recipe: Minestrone in Minutes
• consider weight vs. volume further; discuss why professional bakers weigh ingredients such as flour instead of measuring by volume; do Floating Rice Bottle demonstration with a chopstick, vase, and rice
• look at a variety of cereal boxes to find the note that they are packed by weight instead of volume

Tuesday, November 27

• continue calendar making project and make art and write in numbers for October 2019

• do the estimation wall activity: red onion
• make metric recipe: Sweet Potato Soup
• explain gravity clearly; explore the difference between mass and weight by looking at the website Your Weight on Other Worlds
• explore the difference between mass and volume by looking at and feeling the difference in the mass of identically-sized Density Cubes (this set of 12 contains cubes of acrylic, oak, pine, poplar, steel, aluminum, copper, brass, nylon, PVC, lignum vitae & polypropylene)

Thursday, November 29

Friday, November 30

• continue calendar making project and make art and write in numbers for November and December 2019

• do the estimation wall activity: lemon
• make metric recipe: Strawberry & Rose Sorbet
• discuss density (the relationship between an object's mass and its volume) and explain how a Galileo thermometer works; go outside and come back inside and watch the blown glass bubbles move

• add the Metric Stair to the MLB

BONUS TIME - Friday, November 30

Since our Bird Art Show wrapped up last week and we don't have Science Club again until January (so that all of our creativity can be focused on the Class Play), we used our time today for a few additional fun explorations of mass, volume, density, and buoyancy.

• do the Orange Buoyancy Experiment from Playdough to Plato

We used a lemon and it still worked fine. This is a great experiment! Look at the whole citrus fruit, predict whether it will sink or float, put it in water, observe, take it out and measure the mass. Then peel the citrus fruit, predict whether it will sink or float, put it in water, observe, take it out and measure the mass again. Discuss!

Remember that density is a relationship between mass and volume. Talk about the competing forces on something which is in the water (we had already begun to talk about this with the Galileo thermometer). Think about the Titanic. Its volume did not change when it hit the iceberg but its mass did when the compartments filled up with water. Too many compartments filled up for it to stay afloat, thus the relationship between its mass and its volume had changed enough to make a major difference. Think also about life jackets. Yes, that citrus peel was adding mass but it was also full of air pockets. Look up close at the peel to find the air pockets.

So, would this work with all citrus fruits? I don't know but I would love to find out!

The children found this exploration fascinating. They also wanted to see if the peel would float on its own, which it does, even when the curve of the peel is filled with water. They pushed it all the way down to the bottom of the punch bowl but it still floated back up.

• search the house for two items which have the same mass but one sinks and one floats (this ended up being a Lyra colored pencil and a Teifoc mini brick roofing tile, both with a mass of 11 g)

• design experiments to explore how strong spaghetti and/or linguini are as well as whether the pieces are stronger when arranged horizontally or vertically, based on
How Strong is Spaghetti? STEM Challenge from Frugal Fun for Boys
Strength in Numbers: Spaghetti Beams from Scientific American
• continue to use the scale throughout the experiments and explorations to find the mass of each amount which the pasta could (or could not) hold and add it to data tables in Science notebooks

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