Recommended Age: 5 years and onwards (can be younger depending on the child’s skills and experiences)
Purpose: To practice subtraction that will lead to memorization of the essential subtraction combinations
Level of Parent Involvement: Medium, the adult must present this exercise to the child, once the child has been shown they may work independently
Prerequisites
- The child must be able to count accurately from 1-10 and onwards
- The child must be able to write numbers
- The child must be able to match the numeral symbol with its quantity of numbers 1-10 and beyond
- The child must have had many experiences doing subtraction with the golden beads
- The child has been introduced to the first and second exercises of the subtraction strip board and has practiced working with these materials multiple times
Materials
- The subtraction strip board
- Blue strips 1 to 9
- Red strips with partitions 1 to 9
- 17 unmarked wooden strips
- Prepared subtraction tables
- Pencil
- Subtraction chart 1
Note; if doing this exercise with your child from home you will be using the paper version of the above materials (see resource pack)
Preparation
- None
Steps
- Invite the child, together bringing the materials to the table
- Lay out the strips as per presentation one but this time set out the red strips as well (Lay out the blue strips from longest to shortest on the left side of the board, the unmarked wooden strips, longest to shortest to the right of the blue strips on top of the board and the red strips to the right of the board)
- Ask the child to choose a number, for example 12, and write the number at the top of the blank paper
- Then using the blank strip, child may block out the other numbers
- Invite the child to make 12 as many ways as they can using the blue and red strips
- When all possible combinations have been made, tell the child “now we are going to take away from 12”
- Slide the first red strip to the bottom right corner of the board for example 12-3=9, saying the equation out loud as you slide the strip
- The child then writes the equation on the blank paper
- Repeat for remaining, each time writing the equation on the paper
- At the end all blue strips will be on the left of the board, red strips will be on the bottom right corner (refer to image below)
- Child may check with control chart 1
- Invite the child to choose another number for independent work, they make all combinations, then write the subtraction equations on another piece of blank paper
Variations
- None
