More Multiplication

I didn't end up adding a new times table to learn last week except for the 5x, which students were introduced to at the end of the previous week. 

This week we will continue with 0, 1, 2, 10, 5 and add at least the 11 times.

Please keep practicing facts at home and looking for examples of arrays and groups of things (packages of juice or pop, ice cube trays, the arrangement of gum in a package, etc.).  Even though there is NOT an expectation that students have the facts memorized by the end of Grade 3, it is expected that they understand strategies to help them figure out products.  Practice at home with arrays and making groups of things will help with this.

I will send home more problems for homework this week even though the return rate on last week's work was disappointingly low.  Students will not be asked to complete much work, but it will all be good review for them.  If you could ask to see it and encourage them to complete it, I would appreciate it.

Have a great week!

Multiplication continued....

Sorry for the lateness of this post.  Sunday ended up being my Family Day holiday.

This week, we will continue with the concept of multiplication focusing more on how useful multiplication is as a computation strategy.  Therefore we will be looking at some simple, real-world problems and word problems that involve multiplication.

Last week, we introduced the following timestables: 0, 1, 2, 10, and 5.  Since we were not at school on Wednesday, the 5 times ended up being introduced on Friday by a substitute teacher who was covering for me.  I will check in with students on Tuesday to find out what they understood.

Last week, I also introduced the multiplication table to the class and students shaded in the rows and columns of facts that they've already learned. We reviewed how to use a multiplication table to find a fact that they are looking for.  Though the goal is to have students understand how they can figure out products (answers to multiplication questions) on their own, it is still very helpful to know how to use a multiplication table.  The table is also useful for helping students recognize patterns and relationships between the products of different factors (numbers that are multiplied together).

This week, we will review the 0, 1, 2, 10, and 5 times, and add the 11 times and 9 times.

In addition to working with our multiplication facts, report card time is fast approaching so I will be doing some assessment with students to see how well they understand the various concepts we have worked with since the last reporting period.  These concepts include place value, addition, subtraction,  and measurement with centimetres.

I will create a review document for students to work on for homework this week.  If you haven't had a chance to give your child any practice with the concepts we've been working on then this will give them a good review.  Please don't panic though if your child is stuck on some things.  I do try to circle back to review concepts as we go, but sometimes it seems that if they don't use something (or aren't thinking about something) on a regular basis, they lose it.  That's why giving them a few questions here and there at home is really helpful.  They can be addition/subtraction or multiplication facts that you put up around the house or in their lunch box; involving them in discussions about estimating costs and totals; skip counting with coins (or bills!); counting the number of carrots in a bag and figuring out how many carrots would be 5 bags (that's multiplication!).

There are lots of multiplication games online that give students good practice with their facts.  There are a number of games at Multiplication.com and the rally game, linked below, is one of them.  The games on this site allow you to choose more than one timestable to work on in one game.  So, students could choose all of the tables that we worked on last week and will introduce this week.

Multiplication Rally Game

There are lots of other multiplication games on sites such as Mathplayground.com, abcya.com, and fun4thebrain.com.  Some may require apps that you will need to download and some games may take a bit to download (or maybe my 9 year old computer is slow!).

Have a great week everyone.

Multiplying Menaces

This week our focus will be on multiplication.  Please see last week's post about how important it is for students to understand the meaning of multiplication and what each factor represents in a multiplication sentence.

So far, we've dealt mainly with rows of objects, so we will also look at how multiplication can be represented by groups of things.

This diagram illustrates the multiplication sentence 3 x 4.
There are 3 groups with 4 little circles in each one. Count them one by one or skip count by 4 to find the total number of little circles.
3 x 4 = 12

Along with continuing our work to understand the meaning of multiplication and recognize when it is useful to use it, we will begin working on multiplication facts.  We will start with easy ones: 0, 1, 2, 10, and 5.  I see no reason why we can't master these this week!  We'll try and see how we get along.  The 0 and 1 times should be super easy; the kids are already familiar with the 2 times since they've been learning doubles addition facts since Grade 1, as well as skip counting by 2; the 10 times are easy to remember because a 0 is placed after the number (which means the place value has increased by one place); and most kids find skip counting by 5 to be a breeze.  That really won't leave us many other facts to learn, especially considering the commutative property..... the fact that 2 x 8 equals the same product as 8 x 2.

Please ask your child about what they're learning in multiplication and feel free to quiz them on their multiplication facts.  Let's aim for 0 and 1 facts on Monday; 2s on Tuesday; 10s on Wednesday; and 5s on Thursday.

Have a great week and Happy Valentine's Day to all!

Multiplication - Repeated Addition and Arrays

We did it!  We finally looked at multiplication at the end of last week.  Phew!  Two things I shared with students are that multiplication is repeated addition (ex. 2 + 2 + 2 is the same as 3 x 2) and we touched on arrays. I showed them the following real-life arrays and how the orientation of each one results in a different multiplication sentence.  This is VERY important since students will need to be able to illustrate the meaning of a multiplication sentence and we are expected to be strict about how they do this.  The first number in a multiplication sentence represents the number of rows or groups present and the second number is the number of things in each row or group.

Even though 3 x 4 and 4 x 3 equal the same product (12), they do not MEAN the same thing.

When looked at this way, this tray for Ferrero Rocher chocolates shows us a 5 x 3 array.....5 rows and 3 in each row.
5 x 3 = 15


 

If we rotate the same chocolate box it shows us a 3 x 5 array.....3 rows with 5 in each row.
3 x 5 = 15

Likewise, an egg carton looked at this way shows a 6 x 2 array.....6 rows with 2 in each row.
6 x 2 = 12

Rotated the other way, the egg carton shows us a 2 x 6 array .. 2 rows with 6 in each row.
2 x 6 = 12

This week, please encourage your child to look around the house to find examples of arrays.  I can see one right now on the keypad of the phone beside my computer!  How many different examples can your child find?  Encourage her or him to name the array according to the examples given above.

Also, even though we're venturing into multiplication, please don't forget about addition and subtraction, particularly with regrouping.  A couple of problems a day will help to keep them sharp!

I haven't added any new websites this week.  There are some games available that involve arrays, but we haven't done enough yet at school to be ready for those, so please just continue to encourage your child to practice addition/subtraction facts, place value, and measurement.

Thanks and have a great first full week of February!