Singapore Math Method for Compensation Subtraction

After years of doing intervention work with subtraction across a zero, I was so excited when I learned about compensation subtraction.  It's also called constant difference.  It helped so many kids and it wasn't just a trick.  They understood why they were doing it!

When I taught larger numbers, I generally reverted to the traditional method, or used many steps.  After spending a really fun week in Cleveland, MS, Lon Hayes sent me an email describing this method of compensation subtraction with larger numbers.  Thanks so much Lon!!

Try this with your class and let me know how it goes!

Singapore Math--Extending a Problem

This was a comment on another post...I just wish I had the original problem!

Today I posted some of the part/whole problems around the classroom for student pairs to go around and make models/solve. I had one kid that needed more of a challenge, so I asked him to write more problems... Here are his two problems: Joe bought 26 chairs. They each cost $7.25. How much money did he have to pay? 

 Logan made 64 chairs. He needs 6 wood planks to make 2 chairs. How many planks does he need to make 64 chairs?

Singapore Math Addition Strategies

We tend to think our children need to learn their math facts--then go to double digit addition, first with no regrouping, then with regrouping.  Once they can add two digit numbers, it should generalize to larger numbers.  But is it that easy?  Lately, during my workshops, I've been asking teachers to see how many ways they can find to add.  I do the traditional algorithm, just to take it out of the mix.  My wonderful North Carolina teachers came up with all these different ways to add numbers together.

We started talking about manipulatives.  Using Zolton Dienes theories, we went from proportional, everyday materials to non proportional materials.  Then we went to lots of our favorite Singapore Math strategies like number bonds (building 10s) and left to right addition (based on place value.

We also talked about other methods that children should be comfortable using--hundreds charts and open number lines.  Finally, we went to partial sums, which I think is a critical, missing piece.  The traditional algorithm is the last piece.

Thanks Murphey Traditional teachers for putting in the work to make this as a teacher anchor chart!  

Anchor Charts

Take an objective look at your room.  What percent of the space is taken up with each content area?  What is taken up with store-bought materials that just becomes wallpaper?  Does math have equal representation? Your walls should reflect your teaching style.  Our walls need to be dynamic and part of our instruction   I strongly believe in anchor charts.

This is an anchor chart used in my old school district

 I wish I could remember where I got this one!!

Anchor charts don't have to be cute.  As a matter of fact, I believe they should be made with your students and should be in the children's natural language.  You may continue to edit them as you continue instruction in that area or spiral back to it, increasing the depth and complexity.  They need to be referenced during instruction so they don't just become wall paper.  Studies show that students look towards these anchor charts, even though they are removed or covered during testing, as a memory trigger.

 This came from a classroom in Holland, MI

Thanks, Jana Hazekamp for sharing these!

You can see lots more on my pinterest anchor chart page.  Pinterest.com/Ricky_Mikelman

Place Value Workstation

 I'll only make a workstation if it can be used more than one way or more at more than one level.  I wanted was working on some workstations for counting and place value for grades K-2 and something I saw on Pinterest sparked this idea.  Kindergarten students made their initials with unifix cubes and counted them, focusing on making tens.

The first and second graders built them with base 10 blocks.  It got interesting as we worked on making trades between 10s and 1s.

To get even higher values, we built names instead of initials.  Need more ideas?  Build spelling words or sight words!

Primary Workstations

I just returned from North Carolina, where we explored number sense through workstations.  There were kindergarten, first, and second grade teachers.
If I'm going to make a workstation, I want to make sure there are options built in (for me and the children) and differentiation in included in the workstation.

                                                       Shape Puzzles

 I used the school die cut machine to cut out shapes and assigned a value.to each.  The kinder and first grade teachers worked with numbers within 10.  

 The second grade standard was working on adding by 10s to 120.  Some teachers went higher!

Changing the task to "Make a picture with a value of 100" really changed it.  It was way more difficult to reach the sum AND be creative.
If I were doing this with children, I would have used more (and better) colors.  We grabbed what was close by.  I think it shows the idea well.  The children also would label the picture, using the names of the shapes and their values.  FUN!!

Why Teach Math?

I just spent two days with Dr. Yeap Ban Har.  I've been in his sessions before but never a two-day intensive workshop.  Here are some of the ideas he shared that really hit home with me.

• The math we teach isn't as important as the thinking skills we teach.  We need to be comfortable and familiar with information and data--how to take it apart and make sense of it.  
• Some people are good and this is easy.  Some people will struggle and may need more help.  But we will work and will all be successful.
• Visualization is a key skill.  It's the minds' ability to see things that are not obvious. 
• Math is an excellent vehicle for the development and improvement of a person's intellectual competencies.  
• It's the conversations (questioning) and natural language we have during math lessons that will make the math come alive and make sense for the child.
• If you have to repeat (reteach) material each year, you won't have time to teach that year's material.
• Howard Gardener listed many intelligences.  The ability to memorize and the ability to follow procedures aren't among them,  They just take an inordinate amount of practice.  
• The goal of a math lesson is the leave knowing more than you started with,

Thanks Ban Har.  I'm tired but it's a happy tired.