La. Admin. Code tit. 28 § CLXXI-503

Current through Register Vol. 50, No. 9, September 20, 2024

Section CLXXI-503 - Number and Operations in Base Ten

A. Count to 120, starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral.

B. Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases.

1. Ten can be thought of as a bundle of 10 ones, called a "ten."

2. The numbers from 11 to 19 are composed of a 10 and 1, 2, 3, 4, 5, 6, 7, 8, or 9 ones.

3. The numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to 1, 2, 3, 4, 5, 6, 7, 8, or 9 tens (and 0 ones).

C. Compare two two-digit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols [GREATER THAN], =, and [LESS THAN].

D. 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.

1. Use 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 number sentence; justify the reasoning used with a written explanation.

2. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.

E. Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.

F. Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences), 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.

La. Admin. Code tit. 28, § CLXXI-503

Promulgated by the Board of Elementary and Secondary Education, LR 421044 (7/1/2016).

AUTHORITY NOTE: Promulgated in accordance with R.S. 17.6, R.S. 17:24.4, and R.S. 17:154.