This Warm-up prompts students to compare four different base-ten representations. It gives students a reason to use language precisely (MP6). It gives the teacher an opportunity to hear how students use terminology and talk about characteristics of the items in comparison to one another. During the discussion, ask students to explain the meaning of any terminology they use, such as tens, ones, and the value of digits.
Launch
Groups of 2
Display the image.
“Escojan 3 que vayan juntas. Prepárense para compartir por qué van juntas“ // “Pick 3 that go together. Be ready to share why they go together.”
1 minute: quiet think time
Activity
“Discutan con su pareja lo que pensaron” // “Discuss your thinking with your partner.”
2–3 minutes: partner discussion
Share and record responses.
Student Task Statement
¿Cuáles 3 van juntas?
A
B
C
D
Student Response
Loading...
Advancing Student Thinking
Activity Synthesis
Display Images A and C.
“¿Cómo pueden estas representar el mismo número aun cuando el 3 y el 5 están en lugares diferentes?“ // “How can these represent the same number when the 3 and 5 are in different places?” ( is 53 and so is 5 tens 3 ones. It doesn’t matter which order the tens and ones are written in unless you are writing the 2-digit number. The tens are first and then the ones.)
Activity 1
15 mins
Usemos decenas y unidades para formar 65
Standards Alignment
Building On
Addressing
1.NBT.B.2.a
10 can be thought of as a bundle of ten ones–-called a “ten.”
Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
The purpose of this activity is for students to create a collection of 65 using only 5 towers of 10 and single cubes. Students are told that they can’t create any new towers or take apart any towers. Students recognize that there are only 5 tens and consider how many ones are needed to get to 65. Students may count on from 50 to 65. Students may also apply what they have learned in previous lessons to determine they need 1 more ten and 5 more ones, or 15 (MP2). As students represent their collection, they may show the number of towers of 10 they used and how many ones, including 5 tens and 15 ones, or that they grouped 10 of the ones in some way. This includes clearly marking a group of 10 ones.
Students may label their drawings using numbers, a combination of numbers and words, or expressions (MP6).
Launch
Groups of 3–4
Give each group one bag of connecting cubes.
Activity
Read the Task Statement.
10 minutes: partner work time
As students work, consider asking:
“¿Cómo organizaron su conteo?” // “How did you organize your count?”
“¿Cómo van a mostrar de qué manera organizaron y contaron?” // “How will you show how you organized and counted?”
Monitor for students who represent the count as 5 tens and 15 ones in different ways.
Student Task Statement
Haz una colección de 65.
No puedes separar ninguna de las torres.
No puedes hacer ninguna torre nueva.
Muestra tu colección de una manera que los demás entiendan.
Si te queda tiempo, piensa en otra manera de formar 65 usando los cubos de la bolsa.
Student Response
Loading...
Activity Synthesis
Invite previously identified students to share.
“¿De qué manera cada una de estas representaciones muestra 65? ¿En qué se parecen estas representaciones? ¿En qué son diferentes?” // “How do each of these representations show 65? How are these representations alike? How are they different?” (They all show some tens and some ones. One shows 15 ones and the other shows 10 ones in a group and then 5 more ones. One shows an expression and the others don't.)
Activity 2
10 mins
Formemos 37 de diferentes maneras
Standards Alignment
Building On
Addressing
1.NBT.B.2
Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:
Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
The purpose of this activity is for students to represent 37 with tens and ones in different ways. It is not necessary that students find all the ways to represent 37. Students should see that the number can be represented with different amounts of tens and ones. Students are given connecting cubes in towers of 10 and singles, and they represent their thinking on paper using drawings, numbers, or words. Some students may initially represent 37 using 3 tens and 7 ones. Then they notice that they can decompose a tower of 10 into 10 singles and have 2 tens and 17 ones and use this structure to find other ways. Students may represent 37 as , , etc., which are all ways to represent the number. The Lesson Synthesis focuses on representing 37 with different groups of tens and ones.
MLR7 Compare and Connect. Synthesis: After all methods have been presented, lead a discussion comparing, contrasting, and connecting the different approaches. Ask: “¿En qué se parecen las representaciones? ¿En qué son diferentes? ¿De qué manera cada una muestra las decenas y las unidades?” // “How are representations alike? How are they different? How do they each show tens and ones?” Advances: Representing, Conversing
Action and Expression: Internalize Executive Functions. Invite students to plan a method with their partners, including the tools they will use, for decomposing 37 in multiple ways. Supports accessibility for: Organization, Attention
Launch
Groups of 2
Give each group connecting cubes in towers of 10 and singles.
“Acabamos de ver que podemos formar 65 sin usar 6 decenas. Ahora van a encontrar diferentes maneras de formar el número 37. Encuentren todas las maneras que puedan usando los cubos encajables. Después, muestren cada una de las diferentes maneras con dibujos, números o palabras” // “We just saw that we can make 65 without using 6 tens. Now you are going to find different ways to make the number 37. Find as many different ways as you can with the connecting cubes. Then show each different way with drawings, numbers, or words.”
Activity
2 minutes: quiet think time
5–6 minutes: partner work time
Monitor for students who strategically find different ways to compose 37 using towers of 10 and singles including:
Start with 3 tens and 7 ones, and decompose each tower of 10 into singles.
Start with 37 ones and then compose towers of 10.
Student Task Statement
¿De cuántas maneras puedes formar 37?
Muestra cómo pensaste. Usa dibujos, números o palabras.
Student Response
Loading...
Activity Synthesis
Invite previously identified students to share.
Record each way students made 37.
“¿Qué observan sobre las maneras en las que ellos formaron 37?” // “What do you notice about the ways they made 37?” (They both made 37 in the same ways. One student started with all ones and made 1 ten at a time. The other student started with 3 tens and broke 1 ten apart at a time. Each time a ten was made, there were 10 fewer ones. Each time a 10 was broken apart, there were 10 more ones.)
The purpose of this activity is for students to choose from activities that offer practice working with two-digit numbers.
Greatest of Them All
Get Your Numbers in Order
Grab and Count
Launch
Groups of 2
“Ahora van a a escoger un centro de los que ya conocemos” // “Now you are going to choose from centers we have already learned.”
Display the center choices in the student book.
“Piensen qué les gustaría hacer” // “Think about what you would like to do.”
30 seconds: quiet think time
Activity
Invite students to work at the center of their choice.
10 minutes: center work time
Student Task Statement
Escoge un centro.
El más grande de todos
Ordena tus números
Agarra y cuenta
Student Response
None
Advancing Student Thinking
Activity Synthesis
“¿Cómo trabajaron hoy con números de 2 dígitos durante el tiempo de centros?” // “How did you work with 2-digit numbers during center time?”
Lesson Synthesis
“Hoy formamos números de dos dígitos de diferentes maneras. Usamos distintas cantidades de decenas y unidades para formar el mismo número” // “Today we made two-digit numbers in different ways. We used different amounts of tens and ones to make the same number.”
Display 3 tens and 7 ones, 2 tens and 17 ones, 1 ten and 27 ones, 37 ones.
“¿Cuál creen que corresponde mejor al número de dos dígitos 37? ¿Por qué creen que corresponde mejor al número?” // “Which do you think best matches the two-digit number 37? Why do you think it matches the number best?” (3 tens and 7 ones matches best because the digits in the number tell us that there are 3 tens and 7 ones. 37 ones matches best because the number is read ‘thirty-seven.’)
Have feedback on the curriculum?
Help us improve by sharing suggestions or reporting issues.
