Over the last little while in math we have been working on multiplication. We first worked on strategies for multiplying single digits by single digits (e.g. 7×9). Last week, we worked a lot on various strategies for multiplying a 2-digit number by a 1-digit number (e.g. 34 x 6).
Many students today have not mastered memorizing multiplication facts, so until they do, they need some strategies to help.
We learned about many strategies including, but not limited to:
Multiplying is really repeated addition (3×6 is 6+6+6)
Multiplying is skip counting (6, 12, 18)
Stacking (what most of our moms and dads do when multiplying)
Decomposing (34 can be 30 AND 4)
Friendly TENS numbers (take away the zero, add the zero when multiplying by numbers like 40)
NEAR friendly numbers (e.g. when multiplying 39 x 7, do 40 x 7, then subtract one group of 7)
Doubling (if multiplying by 4, you can multiply by 2 first, then double it)
Finger trick for multiplying by 9
Today we began talking about division. We looked at this picture first to help us understand WHAT division is and how it is connected to multiplication.
You can help your child at home by practicing their multiplication facts until they know them by heart.
Also, help them see that division is about equal groups. We have 20 pieces of potato for dinner. If we give each of our 4 family members an equal amount, how many pieces will each person get?
Our posts have been lacking…sorry.
We have been working on patterns. Over the course of many weeks, students have worked with number patterns. We have looked at growing and shrinking patterns, using addition, subtraction, multiplication and some division. We have also looked at input and output patterns in tables.
Recently, we have been working with geometric patterns. There are many hands on opportunities here.
Earlier in December and January we learned how to read and interpret pictographs, circle graphs (pie graphs), bar graphs, and double bar graphs. We have learned to collect data and made our own graphs. You can have your son or daughter log into the Hub. There you can connect to their email and should see results for our data management quiz.
On Thursday and today we looked at the patterns we can use to help us multiply with numbers that end in zero. Today we talked more about WHY these “add zero” tricks work.
We did a “Number Talk” as well today. During our number talks we share different ways we get to answers using mental math (no calculators, no paper). Each number talk has a series of 3-5 questions that will help students link their thinking together as we work toward the questions with bigger numbers. ALL answer are accepted, as we learn from our mistakes. The goal of number talks is for students to learn other strategies of getting to an answer and to look for strategies that might be more efficient than one they used. Here is our train of thought and some of the strategies our students used…
Last week in math, we finally found the solution to a tough problem we have been working through in steps.
As a result of our inquiry on clean water, students have been asking about the Randle Reef project.
Check out our problem:
Last week the students first calculated that the volume of our portable was 140 cubic meters.
We discovered that the toxic waste in the Randle Reef area of Hamilton Bay would fill 4964 portables like ours! YUCK!
This problem was great! We talked about linear measurement (metres), volume (cubic metres), the formula for volume, addition options, subtraction options, multiplication options, and division options. It has even opened the door to decimals and partial numbers which we’ll discuss further next week.
Many students are still using addition and subtraction when solving problems like this, but these big numbers are beginning to help them see why multiplication and division might be more efficient.
Of course with such large numbers, students are allowed to use a calculator once they understand which mathematical operation to use and understand how it will help them to solve the problem.
We have been talking about volume and capacity for the last two weeks. Last week we worked through a very challenging problem. It was a lesson in perseverance. Many students were excited when they discovered how to get to the answer. There were many different strategies used and we learned a lot from each other.
Sudents have been struggling with understanding what volume looks like. For example, would a tube of hand cream be 100mL or 1L. To give them a better sense of what different volumes look like, today we did some hands on math. We made punch! When looking to get the first ingredient, many students realized they had to make two trip to Mrs. Davies to get the Soda… Our collection containers were only 400mL and we needed 500mL.
Now that we have established everyone’s reading levels, we have begun guided reading. This week we are practicing how to problem solve and work independently when Mrs. Davies is unavailable because she is working with another group.
In in our morning brain buzzers we have been reviewing how to round to the nearest ten. Tomorrow we will round to the nearest hundred.
Note: If your child’s face is covered it is because I do not yet have your child’s media consent form.