# Contour Drawing of Function Graphs

The concept of a function and its graph is introduced in the algebra course. By this time, students already have fairly good graphic skills, but not all children are proficient with graphic tools. Some children find it difficult to correlate a drawing on the board with the image in their notebook. They make mistakes with the scale, the unit segment, and confuse the coordinates of points.

Visually impaired children have a special math notebook with larger cells. When constructing function graphs, students sometimes need the teacher’s help to place the points correctly. The notebook for visually impaired students has large cells.

Attention to orientation on the page. Mastering graphic skills is necessary for the development of fine motor skills in the hand. For constructing graphs, we use a pencil or pen. The child should feel the pressure. We do not use a felt-tip pen or marker because their base is too soft.

**Linear Function: The Graph is a Straight Line**

We draw the coordinate system XOY (Cartesian coordinate system).

The student should be comfortable with lines. We start by highlighting the contour. Using a well-sharpened pencil, we place punched points along the coordinate axes. We move along the unit segments. It is better to take one cell as the unit segment. Hand movement helps form a motor representation of the coordinate axes. This work engages both visual and tactile perception channels. The “hand-in-hand” technique can be used, where the teacher or a well-sighted student helps the visually impaired student. It is important to monitor the quality of the lines. All straight lines are drawn using a ruler.

When working with a linear function, it is enough to place two points on the plane and draw a straight line through them. These points can be punched to make it easier to draw the line.

It is essential to explain that the graph of a linear function is a straight line. After multiple exercises, the method of constructing a straight line improves and becomes automated. The student understands how to draw a straight line and what angle of inclination it has to the x-axis. The tasks do not cause difficulties.

For a visually impaired child, constructing a graph takes more time than for a sighted student. This must be taken into account when planning the lesson.

**Quadratic Function: The Graph is a Parabola**

When constructing a parabola, we use the punched points method. Visually impaired students should “feel with their hands” that the graph of the parabola is a smooth line. Comparison techniques can also be used. The linear function is a straight line. The quadratic function is a parabola. When constructing a parabola, it is better to use a pre-made template.

On graph paper, we construct a parabola by points, stick it onto cardboard, and cut it out. The template helps create clear, continuous lines.

Next, we place punched points along the line and obtain a contour drawing of the parabola. We teach students to work correctly with graphic tools and to understand various lines freely.