A student may be born with a visual impairment, or acquire a visual disability through injury or disease. Students with visual impairments may be blind or have low vision. The legal definition of visual impairment depends on the measurement of visual acuity and field of vision.
A person who is legally blind has a visual acuity of 20/200 or less in the better eye after correction, or has a very narrow (less than 20 degrees) field of vision. Individuals who are partially sighted have visual acuity between 20/70 and 20/200 in the better eye after correction.
Other Characteristics of students with visual differences
- These students may tilt their heads consistently to one side.
- These students may have difficulty coordinating eye movements.
- These students may hold reading material close to or far from their faces.
- These students may hesitate to participate in visually demanding tasks and may have difficulty aligning written work.
- These students may have difficulty reading or copying from the chalkboard.
- These students may confuse letters when reading.
- These students may rub their eyes often, squint or blink frequently, or complain often of dizziness or headaches.
Teaching Strategies for students with visual differences
- Address the student by name. Give the student time to focus his or her attention on you before continuing instruction.
- Students should be seated in the center of the front row.
- Let the student know when you arrive/leave the classroom or area.
- Encourage independence whenever possible.
- Describe events the student is unable to see.
- Find a “buddy” for the student. This buddy can assist with classroom activities and assignments as well as with fire drills or other experiences that may be confusing to the student.
- Allow the student extra time whenever possible or modify the length/format of assignments. Visual fatigue can occur during activities requiring continuous use of visual skills. Some signs include: red eyes, rubbing of eyes, laying the head on the desk, and squinting. If the student is able to listen to the information, or demonstrate knowledge in an alternate format, allow the student to do so.
- Use alternate methods of assessing the students whenever possible.
- Inform students of changes in the physical set of the room.
- Tape music for practice at home.
- Bold note or Braille music can be used to facilitate music reading.
- Be aware of environmental sounds in the room and explain any differences in sounds to students with visual impairments.
- Touch is very important for students with visual differences. Provide hands-on experiences whenever possible.
Aids for students with visual differences
- Optical Aids - A magnifying glass can be used to increase font of printed words/music. Students can also enlarge print by using small telescopes to view the board or class demonstrations. This works best when the student is sitting in the center row, a few seats from the front.
- Large-Print Books - A student with better than 20/200 vision who can read letters a quarter-inch in size may use large-print materials rather than braille. There are many organizations who provide this service.
- Talking Books: The National Service for the Blind and Physically Handicapped lends braille and recorded materials to visually impaired persons at no charge. Recording for the Blind and Dyslexic lends recorded education books, including textbooks, to individuals with “print disabilities”.
- Closed-Circuit Television (CCTV): Where large-print books or audiotapes are not available, closed-circuit televisions allow students with visual differences to greatly enlarge printed material and project it onto a television screen. A closed-circuit TV resembles a regular TV with the addition of a camera. It is easy to use: the student places a page of print under the camera and adjusts for focus, brightness, and contrast. An enlarged version will appear on the screen. The advantage of CCTV is that the student is not restricted to large-print materials.
- Computer: Computers can modify the size of print on the screen as well as the contrast and brightness to enhance the student’s ability to read print. They can also be programmed to scan the page at a desired speed and focus on particular parts of the screen. Some computers can read orally, with speech synthesizers transforming print on the computer screen into speech. In addition, many printers can produce documents in large print.
- Specialized Reading Aids: An optacon is a device that converts print into a tactile format, so that it can be read by students with visual differences. Placing acetate over reading material darkens the print and heightens the contrast so the document is easier to read.
- Specialized Writing Aids: Black felt-tip pens product thick lines that are easy to see. Bold-line paper helps students who have difficulty seeing the lines on regular paper, while raised-line paper makes it easier for students to write on the line or construct a graph.
- American Foundation for the Blind
- WebAIM.org - low vision simulations
- Braille Through Remote Learning
- Guide Dogs for the Blind
- Guide Dog Foundation
- National Federation of the Blind: Main Site | Technology Resource List
- V. I. Guide: A guide to internet resources about visual impairments, for parents and teachers. Main site | The lighter side.
- Color blindness
- Alaska Division of Vocational Rehabilitation: What to do when you meet a sighted person
- Reading electronic braille
- Lasik Surgeon Directory - Understanding Color Blindness