In GeoGebra you can make random assignments, which will be corrected by the program itself.
To make an applet is automatically marked, in principle, not so difficult.
You can GeoGebra applets automatically marked low by doing the following:

1. Show axes and grid (right click on the drawing pad and select axes / grid).
2. Indsæt 1 Shot using. -button on the drawing block called a.
3. Set gain to 0.5.
   
4. Indsæt 1 Shot using. -button on the drawing block called b.
5. Set gain to 0.5.
   
6. You can move the sliders by right-clicking on the slider and pull it to, where you want it.
7. Enter the following into the input field (you turn the input field to the submenu show):
   

   a * x   b

8. Try dragging the sliders and see, what happens.
9. Set a to 0 and b 0. (This saves the, da den nu går langs x-aksen)
10. Pull f(x)=… (from algebra) onto the drawing pad.
11. Press -button.
12. Press f(x)=… on the drawing pad.
13. Press the small arrow, which is the sign block.
14. This will give you access to additional features.
    
15. Change the shift amount to Large.
    

    Now create a function with random a- and b-values.

16. In the input field, type the following

    a_1 = Random Medium[-5,5]

17. In the input field, type the following

    b_1 = Random Medium[-5,5]

18. In the input field, type the following

    a_1 * x   b_1

19. Now you have created a function with random a- and b-values.
20. Insert a text on the drawing board using the. -button.
21. Write “Well done!” in the edit box.
    
22. Press OK.
23. Press -button.
24. Press text “Well done!” on the drawing pad.
25. Press the small arrow, which is the sign block.
26. This will give you back access to additional features.
    
27. Change the shift amount to Very large.
28. Right click on the text “Well done!” on the drawing pad and select properties.
29. Under the tab “Advanced” , under “Condition to show object” write
    

    f == g

30. It is automatically changed to

    f ≟ g

31. Press the junction to close the properties.
32. Try dragging the sliders a and b now, to the graph f(x) will be located along the graph g(x).
33. Indsæt en knap vha. -button (in the toolbar).
    
34. Write “NEW FEATURE” in the Caption field.
35. Type the following in GeoGebra script field:

    Select the Active Display[1]
    OpdaterKonstruktionen[]

36. Press OK.
37. Press -button.
38. Remove the algebra window (possibly. under the view menu or by pressing the junction at algebra)
39. Press “NEW FEATURE” and drag the sliders, so that the 2 graphs are “on top of each other”.

Change the color, thickness m.m. for graphs

1. Press -button.
2. Pressure on the graph(line) for f(x).
3. Press the small arrow, which is the sign block.
4. This will give you back access to additional features.
   
5. Change the color, such as blue.
6. Make the line dotted.

Change the color, font size m.m. the button.

1. Press -button.
2. Right-click the button.
3. Choose properties.
4. During the tabs Text, Color and Style can change most things.
5. Be aware of, to see Colour choosing color, respectively. background color and foreground color by pressing: