Maths plays a crucial role in helping children with vision impairment understand not just number, shape and size, but their understanding of the world. Mary McDonald explains
Sighted children's learning is constantly reinforced by the colours, shapes, objects, facial expressions, images, animals, landscapes, and architecture they see.
Children with a vision impairment have greatly reduced opportunities for this incidental learning. So maths questions offer great opportunities to reinforce concepts, fill any gaps and extend a child’s knowledge.
For example some children need to be shown that a rugby ball is not round, or that there are 52 cards in a pack and that half of them are red.
Many blind and partially sighted children need additional help from their teacher to develop a secure grasp of numerical concepts. A young sighted child soon appreciates that rearranging objects on the table doesn’t change the number of objects present. Where a child can only see part of the table or a few of the objects at one time, or can only access them by touch, this may not seem so obvious.
Children with vision impairment often wish to work with tangible objects for longer than their peers, to develop their sense of number and pattern, square numbers and factor pairs. Use counters or bricks to illustrate that prime numbers can only be divided by themselves and one. It is easier to keep track of cubes or counters in a contrasting coloured tray.
Blind children may prefer to use a peg board such as from a solitaire game, as pegs can be felt more easily than counters without rearranging them. An abacus can also be useful for early counting, pattern and sequence activities.
Some blind and partially sighted children are less likely than their sighted peers to have independently paid and received change in a shop. And because price labels are often too small to read, some children with a vision impairment need more input from teachers and parents to develop a sense of the relative value of everyday products.
Learning to recognise and discriminate between coins and notes is an essential independence skill. Use real money – it offers tactile clues such as ridged edges and weight, unlike plastic money which feels very different. Insist they give it back!
RNIB's online shop sells products to help with handling notes and coins. Involve the child's habilitation worker and parents so that the child develops a consistent approach to learning about money.
For written work some learners need a bigger bolder decimal point and some find it helpful if it is highlighted with fluorescent marker. If you are producing your own resources then consider an alternative to using the full stop as a decimal point: insert a special symbol that will be a larger dot, centred vertically. The specialist teacher for vision impairment can advise.
Good vision makes it much easier to estimate length and gain a sense of relative size. Blind and partially sighted children may need many additional meaningful opportunities to practise measuring and estimating, and ordering objects by size. As well as being essential mathematical concepts, these skills really help when children are learning to get around independently.
You can buy a tactile ruler from RNIB's online shop. The specialist teacher for the visually impaired will be able to teach the tactile method for using the ruler.
Some children with impaired vision are only able to measure accurately to within 0.5cm. Candidates sitting public examinations using modified large print or Braille papers are likely to be allowed an error margin of 0.5cm when measuring or drawing.
Transparent measuring equipment can also be adapted with bold marker pen, Bumpon stickers or tacti-mark. Some children find it easier to measure liquid if you add food colouring to make it easier to see.
Plastic trays divided into sections to teach Hundreds, Tens and Units.
Magnetic place value cards for building up two and three digit numbers – hundreds, tens and units overlay each other. These are particularly useful if a partially sighted child uses a sloping work surface, to bring their work closer.
One hundred squares in a large font or overlaid in braille using Velcro strips. Tiles can be blanked out using Blu Tack or with blank tiles that you attach with Velcro. Ask the child to work out which numbers are covered. The same adaptations can be used for bingo.
Easy-to-see or braille number lines with some numbers pre-marked to help with understanding subtraction and negative integers.
Large print number fan for group activities – some children need someone to tell them what numbers are being displayed. Matt fans are easier to see than ones with a glossy finish.
Fractions boards – labelled in braille if necessary. Make sure that the per cent symbol and ratio colon can be read easily.