Addition using Place value and Standard Algorithm
objective:
- able to solve single digit,double digit,three digit addition with carry over.
- able to solve single digit,double digit,three digit addition without carry over.
- To analyze how to solve addition using standard algorithm.
- Able to compare the flat long units in solving addition.
Materials:
geogebra file
process:
The whole classroom was divided into small groups based on the level of the learner, each group contains 8-10 students and a facilitator. Based on the level of the students the facilitator try to help the students from their basic concept/previous concept. To introduce addition to students the facilitator planned to use the flat long units and connect it to addition with flat long units, standard algorithm. The same concept was tried to explain in different methods.
Addition without carry over
Addition of the numbers less than 10.
The facilitator used a geogebra file which consist of flat long units to explain how the units of two different numbers gets added when the sum is less than 10.The students had given the representation of place value to find the sum and represent the answer in flat long units. Later it was connected to the standard algorithm of addition to solve the sums. It helps students to co-relate that both the answers are same. At the end some of the sums was given to practice it.
For the same concept different methods were used like grouping the students and telling them to write the numbers in a chit and passing the chits to different students to solve it,students themselves had to choose the number and solve it, the facilitator gives different representation to all the students and have to solve it.
For example: 4+5=9; 3+4=7; 6+2=8.
Addition of the numbers greater than 10.
by recalling the previous knowledge with the students the facilitator asked the students to tell any two digit number for two different students and other students had to write the number and represent in the form of flat long units. With the same numbers the facilitator showed a geogebra file and explained how to add the units and tens and represent the sum in flat long units. The facilitator gives few sums for all the students in the form of flat long units and tell them to solve it. Now the teacher explain how to solve sums using standard algorithm. this helped the child to get exposure to different methods of solving. some different questions to each student were given by the facilitator for the practice.
For example:
16+21=37; 43+51=94; 74+10=84.
Addition with carry over
Addition with carry over for single digit
To explain addition with carry over the facilitator used the geogebra file to explain the concept.
The facilitator shows two different numbers in flat long units and tell students to count total number of units. If the sum is more than or equal to 10 then again regrouping of units into tens and units.
For example : 7+8=15
Addition of two digit numbers
from the previous knowledge of the two digit addition without carry over the concept of addition was introduced. The teacher considered any two numbers for example 18 and 26 and asked the students to represent it in flat long units and add the units and tens. The students came up with 14 units and 3 tens.
facilitator asks the students what do observe in units. Students answers that the units are more than 10 then facilitator asks can we regroup it again? The students answers yes it can be made into tens and units. Later the facilitator explains that that regrouping tens can be taken to tens place and gets added.
Similarly it was explained by considering few examples and few sums was given for the students to solve it.
This method was related to the place value of addition and the standard algorithm was explained to make them understand why we do we take carry in the addition if the ones digit is 10 or more than 10 and why 1 is taken to tens place as carry