Chapter One -- Getting Started

Lesson 1:

Moving the Turtle

• Primitive procedures -- or primitives
• Turtle status:
  • Heading
  • Position
• Commands: statements to do something
  • Change position -- steps
    • FORWARD           -- FD
    • BACK                     -- BK
  • Change heading -- degrees
    • LEFT                      -- LT
    • RIGHT                   -- RT
• Turtle modes:
  • Draw mode            -- DRAW
  • Empty mode       
• Command formats:
  • Keywords
  • Inputs (parameters)
  • separated by a space
  • terminated by <Enter>
• Wrong commands
  • Error messages

Activities: Try the following commands

1. DRAW

FD 30

RT 90

FD 40

2. DRAW

FD 5

LT 30

BK 60

RT 180

3. DRAW

RT 45

FD 80

BK 80

LT 90

FD 80

BK 80

5. To see what the command HOME does, move the turtle anywhere on the screen and then enter HOME. Describe how HOME is different DRAW

6. Enter the following groups of commands.

   DRAW

   FD 75

   BK 75

   RT 30

   FD 75

   BK 75

   RT 30

Look for a pattern. Continue this sequence of commands until you have a design you like. Record the commands you used.

Exploration:

Take the turtle for a walk all over the screen!

1. Can you get the turtle up to the top of the screen?

2. Can you get it to the top left and top right corners?

3. Can you get the turtle to return to its home in the middle of the screen when it is tired from its long walk?

Don't worry if you lose your turtle. Just enter DRAW and press <Enter> to bring the turtle back to its home position and ready to begin again.

 

 

 

Lesson 2

Looking at the Logo Screen

• Two windows

  • Graphics window -- where the turtle draws

  • Listener window -- where you type

• Change the window size and location

• Edit commands

  • <Enter>

  • <Backspace>

  • <Delete>

Activities:

• Send the turtle backwards to find out how many turtle steps it is to the bottom of the graphics area. Don't let the turtle disappear from view. What is the distance?

• You know exactly how far it is to the bottom of the graphics area. Send the turtle to the bottom of the graphics area again. Then have the turtle draw a border around the graphics area. Record the commands you used.

• Turtle Game

Move the Listener window so that it covers the Graphics window.

 

Now enter the commands below. You will not see what the turtle is doing.

DRAW

BK 95

RT 45

FD 21

BK 42

FD 21

RT 90

FD 21

BK 42

LT 45

FD 30

After you have entered all the commands, move the Logo window back to where it was. Look at what the turtle has drawn. Sketch what you see.

 

Exploration:

Figure out how many turtle steps it is from the bottom left corner of the Graphics window to the top right corner.

 

Lesson 3:

Exploring Angles

• Three steps
  • Predict  (paper work)
  • Program
  • Compare

 1)    DRAW                 2)    DRAW             3)    DRAW

        FD 50                          FD 70                      FD 45

        RT 20                          LT 60                       LT 37

        FD 50                          FD 70                      FD 45

Activities: after class Page 14: A) through H)

Exploration:

Load the Logo Works file named CONNECT. To do this

1. Select Load → into Workspace ... from the File menu.
2. Go to the LOGOWORKS directory (where you keep your Logo Works files).
3. Double-click on the file named CONNECTE.LGO

(The Logo Works files are included on the Terrapin Logo CD and will normally be found in the Terrapin Logo directory.)

The turtle will draw a picture with several numbered "dots" on the screen. Move the turtle around the screen by connecting the dots in numerical order. Try this again, but connect the dots in reverse order.

 

Lesson 4

The Right Angle

• Right angle, square angle, 90 degrees
• Multiple commands on a line
• Shortcut -- command repetition
  • up arrow to repeat the previous command

Activities

• A), B), C), D), E)
• Steps: paper work; program; compare

Lesson 5

More about the Turtle

• PENUP -- PU
• PENDOWN -- PD
• SETPC -- set pen color
• SETBG -- set background color of the Logo screen
  • Sixteen colors are numbered from 0 to 15
• PENERASE -- PE
  • Change the pen to eraser (not erasing)
  • To erase a line:
    • PE -- change to eraser
    • Draw over the line to be erased
• HIDETURTLE -- HT
  • hide the turtle
• SHOWTURTLE -- ST
  • Show the turtle

Activities:

• A)  B)  C)  D) E) F)

Lesson 6

Predicting the Outcome

• Help understand the Logo language
• Steps
  • Predict -- paper work
  • Program -- Logo code
  • Compare result
• Strategies:
  • Self predicting
    • Move the command window to cover the graphics window
    • Enter commands
    • Predict outcome
    • See the result
  • Peer-programming
    • work with a partner
    • Use HT and ST commands

Activities:

• A)  B)  C)  D)  E)

Lesson 7

Working with Large Numbers

• Wrap around the screen if the turtle goes beyond the screen
  • DRAW
  • FD 500
• Wrap may be around the screen multiple times
  • DRAW
  • RT 5
  • FD 5000

Activities

• A)  B)  C)

Lesson 8

Putting it all Together

• Clear the screen (DRAW) and place the turtle at its home position (DRAW, HOME)
• Change the turtle's position -- FD, BK
• Change the heading -- RT, LT
• Enter Logo commands
• Edit Logo commands
• Pick up (PU) and put down (PD) the turtle's pen
• Draw various angles
• Draw a square
• Repeat commands (up arrow)
• Erase a line -- PE
• Hide the turtle -- HD
• Show the turtle -- ST
• Change the pen color -- SETPC
• Change the background color -- SETBG
• Steps of programming
• Wrap around screen
• Load and save Logo files