More Addition with Two-Digit Numbers

Over the last few days, we've continued practicing our addition and subtraction of groups of ten from two-digit numbers.  Today, we began the next step in our learning, adding with two different two-digit numbers.

Sitting on the carpet we received a group of ten frames to use with the person sitting next to us.  We began by making one number using the ten frames.  We then made a second number.  These two numbers were the addends for our number sentence.

For example:

21 + 17 =

We then grouped all our full ten frames (or groups of ten) together.  Doing this gave us two separate groups-our tens group and our ones group.

20 + 10 = 30

1 + 7 = 8

We could then add our two groups together to come up with our answer.

30 + 8 = 38

We continued practicing with different numbers using the same process.  By the end of the lesson, most of us were really beginning to understand double digit addition.

We will continue practicing using the ten frames to assist us with our understanding, and then we will move onto a bit more abstract manipulative, base ten blocks.  Our goal is after practicing with concrete materials, we will be able to solve addition questions without them.

The Six Geographic Regions of Mexico

In Theme Studies, we are learning all about Mexico.  For the last two weeks, students have been learning about the six geographic regions that make up the country.  Together we've read from a couple of books to give us an overview on the land and vegetation in Mexico.  We then got together in small groups to learn about one region in more detail.  

There are six regions:

1)The Central Plateau

2)The Central Highlands

3)The Northwest Deserts

4)Yucatan Penninsula

5)The Mountainous South

6)The Tropical Lowlands

Each group got information on the region that they chose and using this information built a relief.  They then did a brief presentation on their region to explain to the whole class what their region was and some of the things they included.  After each group got a chance to present, we then put the regions together.  We knew that together they formed the entire country, but other than that, it was just like a big puzzle.  Finally, we figured it out!

Here are the different groups with their regions.

Here we are doing our presentations.

Putting the regions together.

 Our finished product!

Learning About Our Brains

Room 20 has been given a special treat.  Over the last two days, Mrs. D. Lockhart has been visiting us to teach us all about our brains.  

We've learned about three different parts of our brains.  The front part of your brain is called the pre-frontal cortex (or PFC for short), and it helps us function.  It allows us to read, think, and be smart.  We also learned about our amygdala.  This part of our brain controls a more basic function in our bodies, the flight or fight response.  When we get upset or scared, we can react in three ways.  We can fight, we can run away (or flee), or we can freeze.  Mrs. Lockhart referred to these as 'the three fs'.  The last part of our brain that we talked about is the hippocampus.  This part of our brain is like a scrapbook.  It holds all our memories.

We discussed how when we get really upset, it's like when we shake up a bottle full of glitter.  Our brain is so scattered that we cannot respond properly.  When this occurs we are thinking with our amygdala, and therefore we can only react in three ways.  We can fight, we can flee, or we can freeze.  (We really liked the actual bottle full of glitter that Mrs. Lockhart brought to help us visualize).  When this happens we need to do things to help us calm down so that we can think with the "thinking" part of our brain, the PFC.

Yesterday we read a fantastic story about a little girl who got very mad and had to calm down.  This book gave us some ideas of how we could do the same thing when we get angry or upset.

Today Mrs. Lockhart came back to talk about our brain some more; however, she was not alone.  Today we had a special guest.  Mrs. Stevenson joined us, and Mrs. Lockhart told us that she is a brain expert.  We reviewed all the things we learned about our brains yesterday then we talked about calming our brains and being mindful.  We practiced some techniques that we could do to calm our minds and bodies and be mindful about what we are saying or doing.  

Mrs. Lockhart and Mrs. Stevenson will be visiting again to teach us more about our brains and being mindful.

This is the model we used to show what our brains look like.

Within our model, our pointer fingers are the amygdala.

Mrs. Lockhart showing us a poster of our brain.

Practicing one of our calming activities.

Room 20 would like to wish everyone a great long weekend and a Happy Easter!

(taken during Choice Time)

Adding and Subtracting with Two Digit Numbers

Today we started learning about adding and subtracting with two-digit numbers.  We've begun by looking at adding and subtracting groups of ten from a number on the hundred chart.

Altogether we discussed how we could use a hundred chart to help us with adding groups of ten.  We began by looking at the patterns in one whole column.  We saw that in each column on the hundred chart the only digit that changes is the digit in the tens place.  This is because we are adding ten!  We then practiced choosing numbers and adding different groups of ten to them (20, 50, 30, etc.).  After we practiced adding, we then asked how we think we would use the hundred chart to help us with subtracting groups of ten.  We knew that you could use it the same way, but instead of dropping down a row (or two, or three), you go up a row for each ten jump.  Now we practiced subtracting groups of ten from a two-digit number.  We used the SmartBoard to help us visualize the jumps as we went.  All we had to do was tap the numbers and they would turn red.  This helped us keep track of our tens as we counted.  

Soon we were ready for the next step.  We sat in a circle around the carpet and selected a popsicle stick from a bag.  Each popsicle stick had a number between 1 and 50 on it.  Before we began we had selected a rule for our game.  We started with the rule of adding ten, so to each stick that was drawn the person had to add ten.  After we went around the circle, we decided to change up our rule.  This time we tried subtracting 20.  We continued using the hundred chart on the SmartBoard to help us.

This afternoon we revisited this by doing a quick practice with the hundred chart then practicing the concept through the use of a math game.

Students will get the opportunity to practice with a partner again (with a different game), then we should be ready for some individual work with this concept!

Register Tape Number Lines

Over the past couple of days, we've been working on building number lines to further develop our understanding of number sense and place value. 

We began by making a number line all together.  Mrs. Deyoe placed 0 on one end of the register tape, and 100 on the other.  She then folded it and asked what number would be half way between 0 and 100.  We quickly decided it was 50.  We then added the groups of ten.  After some thought, we decided to use the width of our hand as a good guideline to help us evenly space the tens.  After we had finished numbering our register tape, Mrs. Deyoe brought out some pretty cool dice.  They were large, foam, place value dice.  Mrs. Deyoe began by rolling the tens dice and the ones dice to create a number.  She then asked a student to help her decide where it should go on the number line.  When we had decided where, we added that number to the register tape as well.  After a few turns, the students took turns coming up and rolling the dice to create a number.  They would then find where it would go on the number line and then it would be added.  

After our whole group practice, we were ready to try this activity with a partner.  Each pair got their own piece of register tape with the instructions to add the 0, 100, and then the 50.  These we could do in marker.  We had to add the groups of ten in pencil first (in case we needed to erase them), and once they were checked we could go over them with marker, and we would get our own set of place value dice to use.  Together each partner did the activity the same way we did as a class, they would roll the dice and place the number on the number line.  It was the partner's job who was not rolling to make sure the number went in the right spot.

 Today we continued our learning.  This time, Mrs. Deyoe took the Grade 3 students out into the hall to work on their own number line, while the Grade 2 students remained with Mr. McFarlane to complete register tape number lines independently.  They all did a fantastic job!

While in the hall, Mrs. Deyoe made a new number line.  This time, she took a really long piece of register tape and taped it to the wall.  She then placed a 0 at one end, and a 1000 at the other end.  The next step was to fold the number line and decide what number would be half way between 0 and 1000.  Five hundred was added to the paper.  We then discussed how we couldn't use groups of ten on this number line because it would just be too hard with way too many numbers, so instead we would use groups of 100.  Spacing these properly on the paper was a bit more challenging then then tens, but we soon got it right.  Next we quickly added 50s (150, 250, etc.) to the chart to give us additional assistance with our placing of numbers.  We were ready for the dice!  This time, we got to use the hundreds dice as well.  We rolled the dice in the hall, and students would come up and show where the numbers went.  After a few practice rounds, we once again began adding the numbers to our number line.

By the end of our lesson, we decided that we felt ready to give it a try with a partner.  The Grade 3 students will get a chance to do this while Mrs. Deyoe works on a different activity with the Grade 2s.

  

A Visit from Mrs. Waters

Today, Mrs. Waters visited our classroom to discuss writing.  She's coming back for three more visits and we are going to be working on a new writing project with her, writing restaurant reviews!

During today's visit we made a list about all the things we know about writing.  We even surprised ourselves with all the things we already knew.

We also began discussing what a review was and coming up with all the different restaurants we had been too.  With the number of pizza places on our list, we can tell that pizza is a Room 20 favourite!