Turtle Graphics

Move a "turtle" about the screen. Make it draw geometric shapes. Time-proven path for beginner's programming.
Some simple lessons using THREE applications: Scratch, NetLogo and Python.
These apps in order offer more complex and thus more capable programming environments.
But these lessons are aimed at first-time programmers.

Scratch ver 3

Install ScratchOn-line and off-line installs.
1. Scratch editor and extensions The Stage and Script areas, the Block palette and the pen extension
2. Moving Scratch on the Stage Stage coordinates, draw/remove lines, moving/returning
3. Blocks clip and unclip, action sequence Moving and turning to make a square; eraseall
4. Gliding on a background Sequence of glides, return to start over
5. Repeat loop to draw square Resize Scratch, refine square drawing, initialising
6. Using and changing a variable Square becomes maze
7. Turn sequence into a procedure Making My Blocks using two procedures
8. Make one procedure use another Draw small square outside large square
9. Changing variables for both squares Introducing global or local variables

NetLogo ver 6.1

Install NetLogoGet the off-line IDE.
1. Beginning NetLogo Worksurface - Commanding the turtle - Moving forward and turning.
2. Keeping the commands Writing code - Create a procedure - Running a procedure
3. Direct a turtle Use turtle to navigate a maze.
4. Draw a square The Init procedure - settings check - procedure named, add button to run named procedure.
4A. Draw a pattern of squares Repeating the repeat instruction to make a pattern from 36 squares.
5. Draw a square - Using a Global Variable and initialising.
6. Draw small inside large square. Calling procedures from a procedure I
7. Draw small outside large square Calling procedures from a procedure II
8. Draw squares changing size of both squares Changing values at runtime
9. Draw separated squares Two turtles drawing squares separately.
10. Draw touching circles Turtles can make circles by drawing a 360-sided polygon.
11. Draw circles with increasing size Lots of circles all touching at a point - looks like a cone.
12. Draw lots of circles Six "petals" around a central circle then do 11 above.

Python ver 3.8.5

Install Python ver 3.8.5 Get the off-line IDE.
1. Python Shell and Editor Getting started; getting a turtle drawing screen
2 Writing and saving turtle commands Set folder for py files; moving the turtle