Page 66 - TG_G1_CH6_CHRIS

Check

Questions 1 to 5 include:
• Use the problem solving strategy to solve word problems concerning
2-digits addition and subtraction

After children solve independent practice, make sure they understand how
to count on tens in real-life situations by solving problems 1 and 3 to reinforce
children’s ability to count on tens. In order to make sure that they recognized
how to add tens and ones, guide them to solve problems 2, and 5 to improve
children’s ability to add 2-digit number and ones.

Problem 4 reinforces children’s ability to subtract multiples of ten. Encourage
them to use place value concept to find the difference.

When children finish solving exercises1-5, copy some exercises from the
following additional problems on the board for group or individual work. The
additional problems are based on 2-digit addition and subtraction.

For problem 1, ask: How do you subtract multiples of ten? Encourage them to
use a strategy such as the hundred chart. For Problem 2, Ask: How do you add
multiples of ten? Encourage children to use the count on tens using the number
line.
If children have difficulty, give them some counters, a place value
chart, and a number line. Have them put counters in the place value
EXIT ACTIVITY chart to represent hundreds, tens, and ones to solve the problems.

Additional problem 1
Use the Exit Activity for this lesson to Mia collected 70 eggs from her granny’s farm. She used 20 eggs. How many
reinforce children’s understanding. This eggs are left?
can be used as an informal formative We can use the hundred chart to find 70 – 20. We need to start at 70. If we
assessment. move up two steps, we have 20 less. We have 50 eggs left with Mia.

Additional problem 2
Jane read 40 pages from a book, and then she read 20 pages more. How
many pages did she read in all?
We can recall the addition fact of 4 + 2 = 6, then she reads 40 + 20 = 60 pages.

CLOSURE

In order to make sure children understand the main concept of the lesson, copy the following problem
for group of individual work: Cornelia baked 55 cookies and bought 20 more. How many cookies are there in all?

Children can use the problem-solving strategy to solve the problem as follows: Tens Ones
1. Read and understand the problem: Cornelia baked 55 cookies and then bought 20 more.
How many cookies are there in all? 5 5
2. Make a plan: I can use the place value chart to add. + 2 0
3. Carry out the plan: We add ones to ones and tens to tens. The answer is 75.
4. Check: My math is right. 7 5

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