Blocks game

Use Appendix 1 to prepare the working materials by printing as many copies as you will need.

Divide the students into pairs. Give each pair of students 9 blocks of tens and 9 blocks of units in an opaque envelope.

One of the students shakes the envelope, pokes in without looking, and takes out 7 blocks. The other one takes the rest. Each one writes down the number that they have drawn, and then the students combine the two drawn numbers to find out the sum. The students change the order and repeat the activity.

After that, ask those who wish to write down the numbers and the sum on the white board. Discuss the results with the whole class.

ASK: Why do all groups always get the sum of 99? (the blocks in the envelopes make 99). Why do we have so many different ways to sum numbers? (the students drew different combinations from the tens and from the units blocks). Who has more blocks - the one who has drawn 7 first or the one who takes the rest? (the one who takes the rest). Who gets the bigger number? Does the one with more blocks always have a bigger number? If the students confirm this, challenge them to come up with a way for a person to have more blocks, but a smaller number. If they don't answer, ASK: How is it possible that the person with more blocks have a smaller number? (one block of tens has more units than one block of units, respectively, the smaller number of blocks of tens can actually be a larger number than a larger number of units as individual blocks. Conclusion - the number of blocks does not tell us the number of units) .

Time – 5 min.

Grouping of units and tens

Remind the children of the grouping rules:

10 units make 1 ten.

Illustrate the ratio of 1 to 10 with the picture as well (you can draw it on the board or show it on a slide), asking the students: How many units are in the block? And how many tens are there in the column?

We can present number 10 either as 1 column of 10 squares or as one block.

Tell the students that the tens block (point at the first block) is drawn very slowly and to make it easier for us, we sometimes draw it as one long block (point at the second block).

Students should:

● represent a two-digit number as a sum of tens and units;

● know that one ten is equal to ten units;

● indicate the place of tens and unit digits in two-digit numbers.

• Appendix 1 – Motion cards

• Appendix 2 – Tens and units blocks

• Appendix 3 – Number writing cards

You can cut the blocks with the students in advance so that they can be involved in the preparation of the lesson.

• Appendix 4 - Numbers and arithmetic operations in the decimal number system

Cuisenaire rods

Numberblocks

Base Ten Blocks

https://www.youtube.com/watch?v=tuMdYPB8zt0&ab_channel=JannaRichmond

The activity aims to reinforce students' understanding of representing a two-digit number as a sum of tens and units. The required prior knowledge for this lesson is that students know the numbers up to 100 and can count to 100. Students will work with a variety of manipulatives to be able to represent two-digit numbers as the sum of tens and units. At the end of the lesson, they will be able to indicate the places of the units and tens in two-digit numbers and will be able to regroup tens and units to make addition or subtraction with two-digit numbers easier.

Group work

Co-teaching of a general education and a resource teacher

Use of manipulatives

Learning in small steps

Arts

The resource teacher:

- develops together with the general education teacher the worksheets, the didactic materials and the overall preparation of the lesson;

- prepares the steps for co-teaching (supplementary teaching) with the general education teacher during the lesson;

-supports the work and participation of SEN students during the lesson;

-participates in the group work, partnering all students and supporting the participation and work of SEN students;

- develops an adapted version of the worksheets, if necessary, and supports the implementation of the tasks of the SEN student/students;

- actively uses the specified materials for visualizing and performing mathematical operations - Cuisenaire rods, Numberblocks and Base Ten Blocks.

unit, ten, place of digits

1. Ask the students to take out the envelopes with the ones and tens blocks. Tell them to use the blocks to write the numbers you will show them – 11 and 29.

Ask them:

How many tens blocks can replace 10 units? (1).

How many units can we use to show 2 blocks of tens? (20).

Continue the lesson by solving tasks 1 to 4 of Appendix 4.

At this stage, the resource teacher can use the unit cubes and 10 sticks from the Base 10 manipulative or Cuisenaire rods to help SEN students understand grouping as a process and recall the formation of 10 as being made up of 10 units. When solving the following problems, Cuisiner rods, Numberblocks or Base 10 can again be used.

Doing these exercises, students strengthen their skills in representing a two-digit number as the sum of tens and units and the grouping of tens and units.

Time – 12 minutes

2. Writing numbers without the help of decimal blocks. Write on the board:

4 tens and 6 units is the number 46

Ask the students to go one by one to the board and write down the number for:

● 5 tens - 50

● 8 units - 8

● 4 tens and 6 units – 46

● 6 tens and 3 units – 63

● 8 tens and 9 units – 89.

Ask the students how the the numbers 58 and 89 could be written using addition:

50 plus 8=58 80 plus 9=89

Write on the board and then do tasks 5, 6 and 7 of Appendix 4.

To solve the tasks in the appendix the resource teacher can work with SEN students using Cuisenaire rods, Numberblocks or Base Ten Blocks.

Summarize: In the two-digit number, the first digit is the number of tens. The second digit is the number of units.

Time – 15 minutes

Final round up: In a 2-digit number, the first digit indicates the number of tens, and the second digit - the number of units.

Time– 15  minutes

Place the students into pairs and tell them that they will that way. Student A writes a two-digit number. Student B uses tens blocks to show the number. Student A tells whether the answer is correct. After that they change the roles. Student A uses tens blocks to show the number written by student B. Student B tells whether the answer is correct.

Students have to practice the exercise twice.

Time – 5 minutes