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S-35

The child can't solve a word problem: loses the data and mixes up the operations

Type: verbalType: dyslexic
What the research says
Solving a math problem involves three stages: understanding the conditions with the support of practical actions, diagramming the content and applying the algorithm of arithmetic operations.
Lalaeva R.I. Dyscalculia in Children, p. 172 (2005)
Exercises at home — free
The grid: breaking a problem down into parts
Builds: Seeing a problem as a structure rather than a solid block of text
You need: paper with a grid drawn on it (4–5 cells), a pencil
  1. Read the problem: “Mom bought bread for 7 rubles and a bun for 8 rubles. She handed over 20 rubles. How much change did she get?”
  2. Fill in the grid together: cell 1 — bread: 7, cell 2 — bun: 8, cell 3 — handed over: 20.
  3. Cell 4 — question 1: how much together? Cell 5 — question 2: how much change?
  4. After a few exercises, the child fills in the grid on their own.
  5. Solving starts with finding the question, not with the numbers.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 171
Find the question in the problem
Builds: Understanding the goal of a problem
You need: cards with problems and possible questions
  1. Give the text of a problem and three possible questions.
  2. The child picks the right one and explains why they rejected the other two.
  3. The reverse: the adult gives the data — the child comes up with the question.
  4. A child who can't find the question starts calculating with whatever numbers come first.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 171
What's missing from the problem?
Builds: Being able to find the missing piece of data — preparation for equations
You need: cards with problems that have a missing number
  1. A problem with a gap: “Dad planted apple trees. Today he planted some pear trees too. Now there are 15. How many pear trees?” (the number of apple trees is missing).
  2. The child pictures it: what there was — what changed — what there is now.
  3. Figures out which piece of data is missing and puts it into words.
  4. This is the hardest exercise — and that's exactly why it's especially useful.
Lalaeva R.I. Dyscalculia in Children, 2005, pp. 171–172
Act out the problem with objects
Builds: Understanding the operation through a concrete action
You need: checkers or counters in two colors, Explain Math to Me number frames
  1. “Dad planted 8 apple trees” — lay out 8 red checkers.
  2. “Today he planted some pear trees — now there are 15” — add green ones up to 15.
  3. “How many pear trees?” — the child counts the green ones.
  4. Number frames: red in one section, green in another — a visual diagram.
  5. Only through physical action does the child understand why this is subtraction and not addition.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 172
Draw a diagram of the problem
Builds: A diagram keeps the structure and frees up working memory
You need: paper, a pencil, Explain Math to Me number frames
  1. After acting it out, draw a concrete picture (apples and pears).
  2. Simplify: instead of a picture — circles, arrows, numbers, a question mark.
  3. Number frames are a physical prototype of the diagram: show the similarity.
  4. The diagram should cover all the data in the conditions.
  5. Once the diagram is drawn, the child chooses the solution from the diagram, not from memory.
Lalaeva R.I. Dyscalculia in Children, 2005, pp. 172–173
Choose the operation sign
Builds: Choosing the sign is thinking, not guessing
You need: problem diagram cards, paper, a pencil
  1. Show a diagram (numbers, arrows, a question). Offer three sign options: +, −, ×.
  2. The child chooses and explains.
  3. Writes down the calculation and works it out.
  4. Next step: the adult dictates — the child builds a diagram, chooses the sign and solves.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 173
Different words — one diagram
Builds: The child learns to see the type of problem and solve by analogy rather than from scratch
You need: 4–6 cards with problems of the same type, blank diagram templates
  1. Present 4–6 problems with different content but the same structure (all about finding a sum).
  2. The child builds a diagram for each one.
  3. Notices: “Different words — the same diagram.”
  4. The reverse: one diagram — make up different texts for it.
  5. The child starts solving by type rather than from scratch — the basis of automaticity.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 173
Without help
  • Takes the numbers from the problem and adds or subtracts at random
  • Retells the conditions but can't pick out the question
  • Forgets the data while solving
  • Refuses to solve word problems
  • Doesn't transfer the skill to new types of problems