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Math Talks – Episode One

Math Talks – Episode One

For the first episode of Math Talks I used my daughter, Lilly, as my student.  She tends to be my educational guinea pig for many, many things.  Lilly is entering first grade but thinking about numbers more like a second grader.

Here is a breakdown of the discussion:

The talk begins with a dot pattern image flash.  This is an activity that helps kids to subitize (recognize quantities without counting).  I started with this activity for two reasons.  First, as a warm up and a way to get going.  More importantly, I did it to reinforce the question I posed later.  I wanted her to think about the ways to make 7 so my dots were different patterns of 7 (six and one, three and four, five and two).  Later I was going to ask her to try to think about 7 as a group of two and five more so I knew this activity would get her thinking in this way.

Math Talks 1 Dot Image 2Math Talks Dot Image 3Math Talks 1 Dot Image 1

When I explain the activity to Lilly, she immediately asks how fast I’ll flash the dot cards.  You might notice my misspeak as I tell her that it won’t be so fast that she can’t see them and then I meant to say, “. . . but not slow enough that you can count them.”  It is important that kids understand the idea isn’t to count the dots.  They idea is to either immediately know the quantity (sets up to five) or to visualize the picture of known quantities and combine them (i.e. see two and two and two and one and that’s six and one more and that’s seven).

An important part of this section of our math talk is the follow up questions I asked.  By asking her how she saw the dots and how many, it confirms and cements the idea that the total can be thought of as two parts combined.

Math Talks 1 Question

As we get into the meat of the talk, I made sure to write my math story in a context that was interesting.  Lilly’s show of choice this summer was Wild Kratts so I used that as a hook to get her interested and engaged.  The question I posed was an add to, change unknown problem.  That’s teacher speak for an addition word problem in which one of the addends (the quantity you are asked to add to the first quantity) is unknown but you know the first addend and the total.  This problem is trickier than when you known both addends because you have to count up or add up to the total and attend to how many it took to get there.  This is a problem first graders should have skill with by the end of the year.

What you see in the video is a visual of her thinking process while solving.  I used the Show Me app to record her steps and did so after our discussion.  It’s important to note that what you see is an exact match of what she wrote on her paper.  After our talk, I spoke with Lilly about what she saw in her head when she was solving problems like this.  She shared that she is thinking in numbers rather than in pictures.  While that is good, and where she should ultimately be thinking, it is important that she have the ability to work with a picture model as well.  In future talks, I’ll work on modeling her thinking with a picture and relate it to the number models with which she is comfortable.

We wrapped our talk with a discussion about challenge.  This summer I’ve spent a lot of time learning about growth mindset.  I really want to instill in my child, and others for that matter, the importance of attempting challenge, using mistakes as opportunities to learn and the value of effort.  I’m doing that by emphasizing those qualities in the praise and feedback I give.

Here is the podcast and the youtube video is below.  Enjoy!

For more Math Talks, visit the Math Talks page on the menu bar.


First and Ten

I was scrolling through Facebook last night, procrastinating going to bed, when I was reminded that this is a good opportunity to talk about math and football. Knowing the partners that add up to 10 is a huge concept in kindergarten math that very much supports first grade and second grade mathematics in terms of addition and subtraction.

How does that apply to football?

Image courtesy of antpkr at

Image courtesy of antpkr at

Every time the quarterback passes or hands the ball off he gets a portion of 10 yards completed and the commentators always talk about how many more yards to a first down. If you are watching the Super Bowl this weekend with your kindergarten, first, or second grade child consider throwing a little math into the mix. Ask, “How many more yards to 10?” or “How many more yards to the first down?”

This is the perfect chance to bring out the math in our everyday lives!

The simplest math tool you never knew existed . . .

How are you feeling about your child’s knowledge of addition and subtraction facts?  Are you worried that he hasn’t memorized them yet. Worried that his teacher isn’t focusing on facts enough?  Well, if you’re older than 18, you probably learned math very differently than your child is learning math today.  Here are a couple of tidbits that differ greatly from math instruction in “our day” and math instruction today:

1. The Common Core State Standards for Mathematics specify that children should learn their addition and subtraction facts through strategy work, not from drill and practice.

2. The standards outline that, by the end of kindergarten, kids should “add and subtract fluently within 5” which means that they should be able to add or subtract any numbers up to 5 and get the correct answer with relative speed.  By the end of first grade kids should be able to do this within 10 and that not until the end of second grade should they “know all sums within 20 from memory.”

So how can you help your child with math homework if you don’t know how they’re supposed to learn their facts?  I’m just going to lay it out on the table – talk to your child’s teacher first if you’re not sure what to do or how to help.  Also, remember that your job is to help your child “figure it out” not to do the thinking for him.  Beyond all that, here’s an amazing tool you can create and use to help your child at home.

Ready for it?  It’s called a . . . Rekenrek.  If it’s easier, call it a number rack.  Literally translated it means arithmetic rack and it was created in the Netherlands.  It was invented a good time ago to help children understand the number system, develop number sense and improve computational fluency (learn addition and subtraction facts).

Rekenreks are easy to build.  All you need is 2 black pipe cleaners, 10 red pony beads, 10 white pony beads and a piece of foam board (a piece about 4 inches by 8 inches is plenty big).  Cut 2 slits on the short sides of the board, evenly spaced between each other and the edges of the board.  String 5 red and 5 white beads on each pipe cleaner and pull through the slits on the foam board.  It is important to make sure that the bead color lines up on both pipe cleaners.  When completed, all beads should be pushed to the right and the beads on the left should be red and the beads on the right should be white.  See the images below.

The simplest math tool you never knew existed . . .The simplest math tool you never knew existed . . .The simplest math tool you never knew existed . . .


These are easy to build and there is value in having your child build it (with guidance).  On a Rekenrek, each bead represents 1 so by building it himself, your child will see the embedded structure of 5 red and 5 white to make 10 and the overall structure of 10 and 10 to make a total of 20.

So here’s how the Rekenrek can help your child.  When working on facts, typically your child only sees the numeral (the symbol for the number).  Using the Rekenrek allows your child to see the quantity attached to each number.  Through practice your child will eventually come to just know these facts.  What’s more, your child is likely learning strategies for adding and subtracting.  For example, many children learn doubles  (4+4, 5+5) automatically.  Children can use this knowledge to solve near doubles.  Children recognize that in the problem 6+7, 7 can be split into a 6 and 1 to make the problem 6+6+1.  The problem with this strategy is that because children easily memorize doubles they don’t “think” about what the fact means.  So asking them to use the double to solve a close fact isn’t always intuitive.  Demonstrating this on the Rekenrek lets your child literally see the double plus 1.


The simplest math tool you never knew existed . . .

Work with Rekenreks support much more basic understanding of number as well.  Rekenreks help children subitize (recognize small quantities without counting) and work with composing and decomposing numbers.

The simplest math tool you never knew existed . . .

Below are links to 2 activity guides (meant for the classroom) you could use with your child to support understanding of numbers and operations.  They are free!

Using the Rekenrek as a Visual Model for Strategic Reasoning in Mathematics

From the Math Learning Center – an in-depth series of lessons that builds from most basic number sense skills to addition and subtraction activities.

Mathrack Activities and Directions

From Mathematically Minded – a brief description of activities as well as assembly instructions.

Counting by Twos

Counting by twos supports a variety of other mathematical tasks.  Counting by twos allows students to count more quickly.  More importantly counting by twos supports doubling, pairs and grouping for multiplication.  Here are some activities you can do to help your child learn to count by two numbers and understand what it means to count by two.
  • Take turns counting.  You say “1”, your child says “2”, you say “3”, your child says “4”, etc. through 20.  Do the counting again but this time you whisper (your child still says the number out loud).  The third time you just mouth the number but your child still says the number out loud.  This will reinforce the counting by twos skills.
  • Think of a toy that is both small and interesting, that already belongs to your child.  Legos, blocks, cars, etc.  Play a game where you set out a pile and ask your child to figure out how many.  Your child should touch two and count two as he/she pushes them away from the pile.  Also, when he/she is done counting, ask if every item had a partner.  Ask if the group was even (each item had a partner) or odd (one item was left without a partner).  Take turns selecting and then counting piles.
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