We have another great round of shows for you! For this round of eight shows, as we introduced last week, we’ll continue to open each episode with a **Mystery Math Mistake** for each grade level. Then, in third grade, this week begins a run of four shows on number lines, which will be really helpful. Second graders will begin making the super cool connection between fractions and telling time this week, and we’re going to keep going on counting with 10 in Kindergarten and measuring in first grade.

# Teacher's Guide

Episodes 313-314

**April Focus: Mystery Math Mistake**

In the Mystery Math Mistake, our warm up for April, the Math Mights get their strategies all mixed up! Students have to be detectives to see if they can find the mathematical error as we work through the problem. You’ll have great fun watching the shows as students start to look with a critical eye to see if they can spot the Mystery Math Mistake!

### Kindergarten

**Focus: **313: Make 10 / 314: Hidden Cubes

**“I Can” statement:** I can find numbers that make 10 when added to a given number. / I can figure out how many cubes are hidden.

**Extension Activity: **Make a 10 / Kids in the Tent

For episode 313, our Kindergarteners will be doing a Mystery Math Mistake with another story problem. There were 10 fish for sale at the pet store, and someone bought five fish. How many were left? Our friends Simon and Orlando are going to help Mrs. Gray try to figure out how she can correct her problem!

The “I Can” statement is: I can find numbers that make 10 when added to a given number. To start this concept, we look at fingers – in the picture, one hand has five and the other hand has one. We ask questions to get students thinking: *How many do you see?* *How do you see them?* *How many more will it take to get to 10?* Using something like fingers helps students visualize, and fingers are so convenient! They’re never far away (they’re attached to the students’ bodies!) and students can use their fingers to count up to 10. Fingers on hands will help students understand how many more they’ll need to get to 10 as well. Then, we look at different combinations of hands to give students practice figuring out the missing part.* If I have eight fingers up, how many fingers are down to complete that 10? *

A game called Math Fingers comes next. Students draw a card showing a certain amount using fingers on hands, which they have to create on a 10-frame with one color. With another color, students then have to complete the 10-frame, and then write a number sentence: 10 = ___ + ___. There is also a sentence stem to complete: *If I have ____, then I need ___ to make 10.*

For their extension activity, the students play Make a 10 with a Counting Buddy, filling in the parts of 10 as we did in the show.

Moving on to episode 314, we’re going to be doing another Mystery Math Mistake. This was one of the most fun shows for us to create – watch it and you can probably see why! The Mystery Math Mistake is another story problem where there are seven marbles on the table and three rolled away. How many marbles are left on the table? Simon and Orlando help Mrs. Gray to get that straight!

The “I Can” statement is: I can figure out how many cubes are hidden. Kids in this episode are going camping! We set the scene and explain that, when you’re camping, some people might be in the tent and some might hang out by the campfire. In our scenario, 10 people are camping. Some are in the tent, and 5 are by the fire. We ask *How many are in the tent?*

On the show, we use a bowl to represent our tent and we have a picture of a fire, which is really fun! If we have 10 friends, and we know that 5 are by the fire, we can figure out that the other 5 are in the tent because 5 + 5 = 10. We use a comparing tower with 10 cubes in it to help students see the missing part. We can put our 5 friends next to the tower and see how many more we need to make 10.

The same concept can be applied using a 10-frame as a tool. If we have a certain number of friends that are in the tent, and a certain amount of friends that are by the fire, can we use the 10-frame to help us solve it? Students then start to do different number sentences. If they know there are 4 people by the campfire, then 6 must be in the tent, so 10 = 4 + 6.

We then talk about how making 10 with connecting cubes is the same as making 10 with a 10-frame. Mrs. Gray shows the two manipulatives side by side, so students can see 4 red and 6 yellow counters in a 10 frame and then see how the same combination looks with 4 snap cubes of one color and 6 of another.

Of course, students have a fun game to play called Kids in the Tent, where students are going to see the different people that are by the fire, and they have to figure out how many kids are in the tent.

### First Grade

**Focus: **313: Measuring with Tools / 314: Measuring with Different Units

**“I Can” statement:** I can measure length with tools. / I can measure the same object using different units.

**Extension Activity:** Measuring with Tools / Measuring with a Tool

In show 313, we’re continuing our measurement unit in our first grade shows. We have a Mystery Math Mistake using a two-digit plus a two-digit number from a previous show talking about the “make a 10” strategy, or making the next decade number. Students are going to have to find an error in how D.C. is decomposing numbers.

The “I Can” statement is: I can measure length with tools. To open the show, we show snap cube towers of two different lengths and a pencil. We ask our two engagement questions: *What do you notice? What do you wonder?* This gives students an opportunity to use some of the vocabulary and the words they may have learned before to create descriptive statements comparing the three objects. For example: The purple tower is longer than the yellow tower – or – It looks like the pencil is the same length as the purple tower. As students look at the objects, they’ll arrive at a lot of this vocabulary. We also ask the students to describe the length of the pencil based on the two other comparison objects – a purple cube tower and a yellow cube tower that are different lengths.

Next, we start working on measuring the length of creepy crawly friends. We have lots of different creepy crawly things like a beetle and a dragonfly, and we have a line showing the length from endpoint to endpoint. This allows students to see how we measure that length for those different creepy crawly critters.

We’ve always talked about lining things up from endpoint to endpoint when you’re about to compare, but what happens if you line something up, say with a length of snap cubes, and you were to push the pencil so it may not be at the endpoint of the snap cubes? We talk a lot about that in this show! Students have to know that, as long as you’re looking at the unit that you’re measuring with, and you can see that full unit being measured, you can count that idea.

But what about paper clips? This measuring tool is a little more tricky. We talk about how paper clips should be lined up if we’re using them to measure an object. Paper clips move a lot because we don’t have them hooked together, but we can talk about what is the same and what’s different between measuring with paper clips versus snap cubes.

Finally, on the show, we then have a Math Might notebook that some students have measured, but we see that some students’ measurements aren’t lining up. There might be spaces or gaps between the paperclips, sometimes the paperclips overlap, etc. This gives kids an opportunity to see if they’re able to figure out how to measure the notebook most appropriately.

Our extension activity gives students more practice measuring with tools.

As we move into show 314, students are going to continue with this measurement concept after another Mystery Math Mistake, once again featuring D.C.

The “I Can” statement is: I can measure the same object using different units. To kick this off, we do another *What do you notice?* *What do you wonder?* This time, we have two rows of cubes matched up to a marker, but you have to look carefully because some are centimeter cubes and some are larger snap cubes. We can see that we have the same length of an object but we have two different units that we’re measuring by.

We bring this into the show by talking about three different measurement units – small paper clips, large paper clips, and small or connecting cubes. In our show, we have a shoe that we’re measuring and we set up scenarios which will prompt kids to think about the accuracy of how someone is measuring. Can you mix small cubes with large cubes to measure? That probably isn’t very accurate because they aren’t using the same unit of measurement. This is the big idea we’re trying to get at in this particular show.

To help kids practice seeing accurate measurement, as well as critiquing the reasoning of others, we show different objects being measured in different ways. Kids have to decide if they agree or not, and give their own reasoning. This is also the extension activity, and students will be measuring with different units and then they can compare how well they’re measuring one unit based on another.

### Second Grade

**Focus: **313: Tell Time with Halves and Quarters / 314: Read, Write and Tell Time

**“I Can” statement:** I can tell time with halves and quarters. / I can tell time, read and write time using A.M. and P.M.

**Extension Activity: **Time Match Up / Tell Time with A.M. or P.M.

In second grade, as we start episode 313, we’re moving away from fractions and using our new knowledge to transition into telling time. For our Mystery Math Mistake, Springling needs everyone’s help! She’s trying to hop on the open number line, like we’ve done in previous shows, but she’s really struggling.

Our “I can” statement is: I can tell time with halves and quarters. We brainstorm what students already know about clocks and telling time. Of course, most students know that you can measure time in minutes and hours. Students will also make note of different kinds of clocks – some are a circle with numbers 1 through 12 around it, but some just show numbers. We will look at the analog clock versus a digital clock, helping kids to make connections and draw parallels. Students might also point out different words they may have learned for time, such as *half past* for 30 minutes past the hour.

In this show, we address a common error that students might make with time, especially with the hour and minute hand, by looking at two clocks that look really similar. But we help students see why both clocks don’t actually read the same time (4 o’clock). For a time like 4 o’clock, students can see the hour hand needs to ON the hour you’re showing, and the longer minute hand needs to be on the 12. That is pretty straightforward, but as time goes on, and when it’s *half past four*, for example, the hour hand won’t be directly on the four, but a bit past, in between the four and the five. This is certainly a more difficult concept for second graders to grasp!

We use a Judy clock on the show to help students see how the hands move, and to help students put the hands where they would go for certain times.

Then, we play a sort game where students organize essential vocabulary (o’clock, half past, quarter till, quarter past, etc.). We bring in the concept of fractions to help students make the connection from previous shows to think about the clock divided into quarters.

For the extension activity, students get to play Time Matchup, where they’re going to be taking the digital clock, matching it to the words of *half past* or *quarter past*, and then show the time on an actual analog clock.

Show 314 opens with a Mystery Math Mistake, again with Springling. Did she hop on the open number line correctly??

The “I Can” statement is: I can tell time, read and write time using A.M. and P.M.

We continue in the show having kids relate to the numbers around the clock, not just in half past or quarter till or quarter past, but also now in the five minute increments. To help with this concept, we bring in what students have learned from the number line, asking them to notice what things are similar between a clock and a number line and what things are different.

We also address the idea of why the times, as we go around the clock, have two numbers – :05 or :00. We then talk about showing different times on the clock, and being able to show where we see 4:15 and why that equals :15. How would you look at something like 12:55? Many students think that that is 1:55 because the hour hand is oh-so-close to the 1. We do a good job of using the Judy clock to help students line it up and see that maybe it’s not quite matched.

Next – a vocabulary lesson! A.M. stands for ante meridiem, and means before midday or before noon. P.M. means post meridiem, or after midday or the afternoon. To get students to apply these new words to their own lives, we have them match up different activities that they would be doing in their daily life at a certain time, and decide if it’s an A.M. or P.M. activity.

It’s then the students’ turn to tell time with A.M. or P.M., based on the scenario that we’ve given them, for the extension activity.

### Third Grade

**Focus: **313: Locate Non-Unit Fractions / 314: Fractions and Whole Numbers

**“I Can” statement:** I can locate non-unit fractions on the number line. / I can work with fractions and whole numbers on a number line.

**Extension Activity: **Guess What Fraction is Labeled / Find the Fraction

Episode 313 for third grade begins with a Mystery Math Mistake, but this time, we’re bringing in Springling, similar to how we did in second grade. Mrs Askew makes an error somewhere, and Imani and Elise help her figure out where that error is.

Our third graders are now moving into fractions. Previously we talked about unit fractions, but now we’re going to look at the idea of non-unit fractions on the number line. Mrs. Askew shows you how to play the game called Number Line Scoot, which is a great game to be able to use in your classroom! It helps students “scoot on the number line” and understand how they can move faster, based on the parts of the fractions.

We do a lot of work here on number lines – locating and labeling fractions such as 3/4 and 6/4. This really helps students understand the common denominator of fourths as we plot those two fractions on a number line from 0 to 2. Students need to understand that, when you see the numerator is larger than the denominator, that fraction is going to be larger than one. We do several examples with common denominators, such as 7/8 and 12/8, to help students discover where to locate and plot them on the number line.

Students also need to be able to create their number lines, so we talk about how to divide up a number line that goes from 0 to 1. If I’m dividing it into eighths, I’ll have 1/8, 2/8, 3/8, and so on until I hit 1, which will be 8/8. If I wanted my number line to go to 2, I’ll need to continue with 9/8, 10/8, 11/8, and so forth.

In the episode, we play a game called Guess My Fraction, where we give hints to see if students can figure out what fraction we have plotted on the number line. The extension activity is similar, called Guess What Fraction is Labeled. The students have to figure out how to label the partitions on their number line to then discover what is actually labeled on that number line.

As we move into show 314 for third grade, a Mystery Math Mistake with Springling on the open number line opens the episode. We want to see if kids can critically look at how the problem is solved and find the error.

The “I Can” statement is: I can work with fractions and whole numbers on a number line. We do something that’s called an Estimation Exploration (which I do believe ended up on the cutting room floor – check out the deleted scenes on the Math Mights website!), where we talk about how an estimate of a fraction that might be too low, just right or too high. Again, we want to see if kids can apply their number sense to what they’re doing.

Then, we have a number line that we want the kids to use to locate and label the fractions. It starts at 0 and ends at 5. Students are now going to see fractions that are larger than whole numbers that they have to plot. We start with halves, and there are also examples of thirds and fourths.

We also talk a lot about which fractions locate the whole numbers. We might know that a whole number is two halves, but do you know what the number two represents? It’s four halves. Three is six halves, and so on. We also want kids to see a pattern – with halves, the whole number is every other fraction. When we look at thirds, every third number is a whole number, with fourths every fourth number is a whole number. Sometimes students don’t get a chance to really slow down with fractions to study them, but allowing time for students to make connections like this is valuable. To help students apply this concept, we look at different number lines to see if students can locate one based on the fraction they see partitioned on the number line.

The extension activity is Find the Fraction. Students have number line A and number line B, and the students are going to have to locate where they see the fractions, just as we did in the show.

I think your students are really going to like our Mystery Math Mistake! It’s a really fun spin on math that helps kids really get interested in trying to find the error. If you want to take it a step further in your classroom, have the students create their own Mystery Math Mistake! If you want to check out more on Mystery Math Mistakes, visit our SIS4Students page to see a whole week’s worth of problems that we did during the beginning parts of COVID. See if you can spot the mistake and let us know!

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