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S-30

The child confuses similar digits when writing: 6 and 9, 3 and 8

visual-processingvisual-recognitionsymbolic-processingmotor-skillsgrade-1
Type: graphicalType: practognostic
What the research says
In optical acalculia, the main mechanism is a disorder of optical and optical-spatial perception. The consequence is impaired differentiation of numbers that contain graphically similar digits (3 and 8, 7 and 1, 2 and 8, 4 and 1, 66 and 96, 36 and 63).
Lalaeva R.I. Dyscalculia in Children, p. 18 (2005)
Intervention work on developing visual gnosis includes: fast and clear recognition of visual images (building visual gnosis); distinguishing similar visual images by color, shape and size; tasks on recognizing crossed-out, overlapping and incomplete outline pictures.
Lalaeva R.I. Dyscalculia in Children, pp. 32–33 (2005)
Exercises at home — free
Find the odd digit out
Builds: Telling apart graphically similar digits
You need: a sheet with printed digits (rows: 6 9 6 6 9 6 9 9 6)
  1. Write a row of digits: mostly one digit, occasionally another (for example, 6 and 9).
  2. The child circles all the “odd ones out” — the ones that are different.
  3. First slowly — saying each digit out loud.
  4. Then faster — silently, against the clock.
  5. Harder: similar pairs 2 and 5, 3 and 8, 1 and 7.
Lalaeva R.I. Dyscalculia in Children, 2005, ch. 4
Build it from the model
Builds: Reproducing a structure from a model — visual-motor coordination
You need: matches or counting sticks (10–15 of them), a model card with a shape
  1. Show a card with a shape made of sticks: a triangle, a house, a fir tree.
  2. Ask the child to count how many sticks are in the model.
  3. Take the card away. The child lays out the same shape from memory.
  4. Compare with the model: “Is it the same? What's wrong?”
  5. Harder: the child lays it out without the model in front of them.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 95
Draw the missing part
Builds: Completing an incomplete visual image — the foundation for recognizing digits
You need: a sheet of paper, a pencil
  1. Draw a shape with one side missing: a triangle without its base, a square without its right side.
  2. Ask: “What does it look like? What's missing?”
  3. The child draws in the missing part.
  4. Check together: “Is it a whole shape now?”
  5. Harder: draw only a corner — the child reconstructs everything else.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 111
Finger shapes — getting the hand ready for writing
Builds: Precise finger movements — the foundation for writing digits correctly
You need: just your hands
  1. Show a finger shape: a house (fingertips joined at an angle), glasses (rings made with the thumb and index finger).
  2. The child copies you.
  3. Once the child can do it confidently, they repeat it with their eyes closed.
  4. Alternate quickly: “house — glasses — house — glasses.”
  5. Link to counting: “Make a house three times, counting out loud.”
Lalaeva R.I. Dyscalculia in Children, 2005, p. 106
Find the pattern's rule
Builds: Visual patterns — the foundation for understanding number sequences
You need: a sheet of paper, a pencil
  1. Draw a row of 6 cells: put a pattern in the first three, for example circle-square-circle.
  2. Ask: “What changes? What's the rule?” The child puts it into words.
  3. The child continues the pattern in the remaining cells.
  4. Harder: a pattern of three different shapes.
  5. Link to math: “There's a rule here too, like in the sequence 2, 4, 6...”
Lalaeva R.I. Dyscalculia in Children, 2005, pp. 112–113
Fist — palm — edge
Builds: Switching movements — training the brain to write digits accurately
You need: just your hands, a table
  1. Put your hand on the table, palm down.
  2. Switch between three positions in turn: fist — palm (flat) — edge of the hand.
  3. First slowly, saying: “fist — palm — edge.”
  4. Speed up, aiming for smooth switching.
  5. First with the right hand, then the left, then both at the same time.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 115
Fingers say hello
Builds: Finger differentiation — each finger works on its own, as in writing
You need: just your hands
  1. The thumb touches the tips of the other fingers in turn: index, middle, ring and pinky.
  2. First slowly, then faster.
  3. Repeat with the other hand.
  4. Then with both at once.
  5. Harder: the left thumb says hello to the right thumb, index finger to index finger.
Lalaeva R.I. Dyscalculia in Children, 2005, pp. 115–116
Playing the piano — fingers one at a time
Builds: Isolated movements of each finger — getting the hand ready for precise writing
You need: a table
  1. Put your hand on the table.
  2. Touch the table with your fingers one at a time: 1–2–3–4–5.
  3. Then in reverse order: 5–4–3–2–1.
  4. Then every other finger: 1–3–5, then 1–4, 1–3, 1–2.
  5. Count out loud with each touch — this links motor skills with the number sequence.
Lalaeva R.I. Dyscalculia in Children, 2005, p. 116
The butterfly flies — both hands together
Builds: Coordination of both hands — spatial control of movements
You need: just your hands
  1. Cross your hands at the wrists, with the backs of your hands pressed together — “the butterfly is sitting.”
  2. On the command “The butterfly is flying,” imitate flapping wings without uncrossing your wrists.
  3. First slowly, then faster.
  4. Stop on the command “The butterfly has landed.”
  5. Count the flaps out loud: “one, two, three...”
Lalaeva R.I. Dyscalculia in Children, 2005, p. 116
Natural materials — hands at work
Builds: Fine motor skills and tactile perception as the foundation of math concepts
You need: a tray with sand or grain, pine cones, chestnuts, pebbles, shells of different sizes, molds shaped like digits and geometric shapes
  1. Pour sand onto the tray. The child draws digits or shapes with a finger.
  2. Give the child digit-shaped molds: the child fills each mold with grain or pebbles, counting them.
  3. Lay out the pine cones, chestnuts and pebbles — sort them by size or type.
  4. Harder: count out exactly 5 pebbles and put them in the mold with the digit “5.”
  5. Feeling the shape of a digit by touch creates a bodily memory of how it is written.
Baryaeva L.B., Kondratyeva S.Yu. Dyscalculia in Children, 2013, p. 48
Geometric insets
Builds: Visuospatial perception of shape
You need: Montessori inset boards or cardboard frames with cut-out shapes, a pencil
  1. The child puts the shapes into the matching holes.
  2. Ask the child to trace around the inset on paper.
  3. “This is a circle. Find something else round in the room.”
  4. Harder: “How many corners? How many sides? What is it called?”
  5. Link it to digits: “How is 6 different from 9? By direction — the way a circle differs from an oval.”
Baryaeva L.B., Kondratyeva S.Yu. Dyscalculia in Children, 2013, p. 48
From analyzing the shape to writing
Builds: A three-stage path to writing digits correctly
You need: digit cards, modeling clay or wire, graph paper
  1. Stage 1 — analysis: “Look at the digit 3. What parts is it made of? Where does it start? Which way does the line go?”
  2. Stage 2 — modeling: the child shapes the digit out of clay or bends it out of wire. They touch it and turn it around.
  3. Stage 3 — writing: the child traces the modeled digit with a finger, then traces it over a model on paper, then writes it on their own.
  4. Check: “Does it look like the model? Where's the tail, where's the curve?”
  5. Repeat with the digits 6, 9, 3, 8 — the very ones that get confused most often.
Baryaeva L.B., Kondratyeva S.Yu. Dyscalculia in Children, 2013, p. 68
Build an object from shapes
Builds: Visual analysis, constructive praxis
You need: a set of cardboard shapes: triangles, squares, circles, rectangles; models: a fir tree, a house, a boat
  1. Show the “House” model card.
  2. Ask: “What shapes is it made of? Name them.”
  3. The child finds the right shapes and lays out the same house.
  4. If the child struggles, show how to turn the triangle for the roof.
  5. Ask the child to describe it: “What shapes is your house made of?”
  6. Change the model. Harder: the child lays it out from memory or invents their own figure.
Baryaeva L.B., Kondratyeva S.Yu. Dyscalculia in Children, 2013, p. 72
Worksheets — print and practice
Finish the row — visual-motor coordination
↓ Download printable PDF (in Russian)
Without help
  • Mistakes in writing numbers down lead to a wrong answer even when the calculation is right
  • Mixing up place values: 36 is read as 63
Related cards
S-06S-25