Triveni Goswami Vernal
Registered Special Educator (A64010)
In the previous blog, I had written about the Subitizing skill (ability to visualize or see the number of items in a small group instantaneously, without having to count them one by one) and the critical role it plays in Dyscalculia and Math Learning Difficulties. I had also shed light on the use of Dot cards to teach Subitizing.
In this blog, I will be writing about the use of Cuisenaire rods and cluster cards for subitizing.
CUISENAIRE RODS are mathematical aids or manipulatives that provide a hands- on approach to explore and learn mathematical concepts.
According to Special Educator, Consultant and Coach, Rebecca Lord, Cusienaire Rods can be used for the following (Decoding Math, https://www.lordmath.com/online-learning/):
1) Moving away from counting individual pieces to Chunking.
2) To view Number as a continuous length and not as discrete/individual measurements.
3) Can build any math fact and multiple digit whole numbers.
Cuisenaire Rods can help the individual create an understanding about Chunking (groups of items), to view number as a continuous length and it can also be used to build upon various mathematical facts and operations.
ACTIVITIES WITH CUISENAIRE RODS:
1) Build Ladder and Count: Take 2 and then you can show, that two x 1s, make 2
2) What is Missing? Take out one rod from between two successive rods and ask what number is missing?
3) For Addition: Take a bigger rod, as a base, such as 7. Then take a smaller number rod like 2. Keep it beside the rod no.7 and ask, how much more is needed to be added, to make 7?
4) For Subtraction: We can take two rods. For example, 10 and 7: Take away 7, what are we left with? Answer: 10
CLUSTER CARDS: Visual Cluster Cards developed by Mahesh Sharma, a Dyscalculia expert and founder of the website, Mathematics for All (https://mathematicsforall.org), resemble playing cards without the numbers printed on them. According to Rebecca Lord Cluster Cards are important in Subitizing in the following ways (Decoding Math, https://www.lordmath.com/online-learning/):
1) “They build on innate ability to perceptually subitize.
2) Develop ability to conceptually subitize.
3) Small sets provide foundation for arithmetic”.
ACTIVITIES USING CLUSTER CARDS:
1) COUNTING: You can show them a cluster card and ask how many of the given shapes (spades, diamonds etc) are there.
2) HIDE SOME OF THE SHAPES: You can hide some of the shapes and ask how many are there.
3) NUMBER BONDS: You can show them a card, for example, 5 and hide 2 with the fingers, and ask how many do we need to make 5…3+2 = 5.
4) DECOMPOSITION: You can show a card and ask the individual to make all the combinations that make the number, by circling the clusters. For example, you show the cluster card of 5, the person can circle various combinations to show what 5 is composed of—0+5, 1+4, 2+3, 3+2,4+1,5+0 etc.
Thus, we see, that besides Dot Cards, Cuisenaire Rods and Visual Cluster Cards can also help in developing the skill of subitizing. In my next blog, I will write about using these tools for Addition and Subtraction.
Author Triveni Goswami Vernal
Triveni Goswami Vernal is an Autism advocate, registered Special Educator (CRR A64010) and an Independent Researcher. Her areas of interest include Autism, Disability Rights, Gender, Art and Northeast studies. She is a mum to an 11 year old on the Autism Spectrum.
The author is also Certified in Dyslexia Teacher Training, Learning Disorders, OG Phonics, Ripples Centre for Enhanced Learning, 2019.