1. Intro CS – Loops & Creating Shapes
Lesson Plan 4

2. Loops, Creating shapes, Goals
Review last week: sprite movement, pens (haven’t learned yet)
Introduce Algorithm - a list of well defined instructions to solve a class of problems
Examples:
Drawing your name using Scratch
Multiplying two numbers
Show square example (no looping)
Show square example (repeat loop)
Show squares/checkerboard example (nested loops)
Show input to collect number of sides, side length, angle to turn
Give exercises for in class practice (show shapes on slides, students try to create those shapes)
Students should come out of this lesson understanding the coordinate system, spatial properties, and how to draw using pen
LP ideas from:

3. Agenda
Review what we learned in the last lesson – how to create a short animation film – what were some interesting things you noticed?
Topics today, we will be stepping back and learning the fundamentals of how to draw in Scratch:
Coordinate system
How to draw lines in Scratch
How to draw a square
How to draw a circle
How to use loops to draw images many times
LP ideas from:

4. Drawing Using Loops Lesson Plan 4
Today we will be learning how to draw shapes and pictures in Scratch.
Let’s review the last lecture and daily project. What were some things you found to be difficult? Some interesting things?
Did anyone have difficulty with the placement of the sprite on the screen? Anyone notice the x-axis and y-axis and go to x/y axis block?

5. Coordinate system
Coordinate system: uses numbers or coordinates to uniquely determine the position of a point. 2 1
Questions to ask:
Show of hands how many of you know about the coordinate system?
How many of the students are familiar with coordinate system? Will we have to review?
Which one is the x-axis, y-axis?
Four quadrants: 1, 2, 3, 4 in C shape
Examples: where do you think the points are?
(0, 0) origin
(100, 100)
(-50, 25)
(50, -25)
(-50, -50)
Ask students for numbers and have them tell you where to draw the point 3 4

6. Drawing Lines
Pretend I’m a sprite, what would you tell me to do step by step to draw a line?
Questions to ask:
Pretend I’m a robot, what would you tell me to do in order to draw a line?
Pick up a pen
Put the pen down on the paper
Pick a direction
Go forward for x number of steps
Pick the pen back up
How do you think we could change color and size of the line?

7. Drawing Squares How would I draw a square? Questions to ask:
Again pick up pen
Put the pen down on the paper
Pick a direction
Go straight until you move x number of steps
Turn 90 degrees and do all over again 3 more times
What’s something you noticed about this code?
What are we repeating many times? How can we simplify the code so it becomes shorter and less repetitive? We want the code to do the work for us, we shouldn’t have to manually do everything.

8. Drawing circles How could I draw a circle?
How do you think we would draw a circle? Think about how many degrees there are in a circle and how many times I would have to turn?
How to change the color and size of the circle?
How to increase the radius of the circle? Change the number of steps you move.

9. Using loops to draw
How could we draw a square 4 times? One in each quadrant
If we wanted to draw a square 4 times how could we do this? One in each quadrant.

10. Example Demo
Let’s look at an example of using a sprite to make a square and circle
Draw Square and Circle
Turtle, walking to do a circle, forward and turning

11. Daily project
By the end of class, each student should create a project that shows a drawing they have done of their initials or other drawing and repeat it in each quadrant of the coordinate system.
Worth 13 points total
Grade Breakdown – Must Include
Points
1) Use pen up/down
1 point
2) Drawing of student’s initials or another drawing
3 points
3) Repeat the drawing in each quadrant
4 points; 1 for each quadrant
4) Change color of the pen
5) Change size of pen stroke
6) Cool shape in middle of screen (using repeat loops)

12. Surveys 1) http://www.surveymonkey.com/s/TEALS 2) Class Survey
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