Oral calculation. 4+6= 5+ =9 -7=3 10-0= 10 10 10 2+8= 3+4= 4 7 10

11 Guess the number It's more than 10. It's less than 12. What number is it？

1 ten 1 one 10 ones is 1 ten 10 ones 1 1 1 1 10+1=11 and makes 11 Using the sticks to show the number Tie these ten sticks together in a bundle. What's the relationship bewteen 10 and 11? 1 ten and makes 11 1 one 10 ones is 1 ten 10 ones digital order table ones tens 1 ten 1one 1 1 1 1 10+1=11

How many sticks? 1 1 1 1 5 3 2 9 1 ten and 3 ones makes 13 digital order table ones tens How do we put the number 12 into the table? Firstly,we put a “1” in the tens place to stand for 1 ten ; Then,put a “2”in the ones place to stand for 2 ones. 1 ten and 2 ones makes 12. 1 1 1 1 5 3 2 9

How many sticks? 2 2 tens makes 20 Tie these ten sticks together in a bundle. digital order table 2 tens makes 20 ones tens The number in the ones place means how many ones, and the number in the tens place means how many tens. 2

Exercise 1、Put them in the digital order table. 2、Write the number sentences. 12、17、14、20 ones tens 1 2 10+2=12 1 2 12 ____ten and _____ones in ___

（ ）tens and ( ) ones ones tens （ ）tens and ( ) ones ones tens

（ ）tens and ( ) ones ones tens ones tens （ ）tens and ( ) ones

Calculation. 10+（ ）=18 10+1= 14-4= 12-（ ）=10 10+3= 19-9= （ ）+10=20 10+（ ）=18 10+1= 14-4= 12-（ ）=10 10+3= 19-9= （ ）+10=20 6+10= 16-6= 11=10+（ ） 10+10= 15-5=

Complete the part and whole models. 10 3 10 7 17 14 15 9 10 4 10

Filling the blanks. 1、 eight ones and one ten is( ) 2、If 1 in the tens place,and 3 in the ones place,do you know the number? 3、20 has ( )tens. 20 has ( ) fives. 20 has ( ) ones.

4、17 is a two-digital-number, it's 1 less than( ),and 3 more than ( ) . 5、Minium two-digital-number is ( ). Maximal one-digital-number is ( ). Add them we can get ( ) 6、If 1 in the tens place, a even number in the ones place, and it's much more than 15,but little less than 20, do you know the number?( )