Welcome to level 4 ### Welcome to level 4 By the end of this lesson, you can: * understand why quotation marks are needed in programming. * put quotation marks in the correct places. * understand error messages about wrongful use of quotation marks. <iframe class="fragment" src="/render_code/4?code=print%20%27Use%20quotes%21%27"></iframe> <aside class="notes"></aside>

Problem ### Problem In the previous levels, you might have come across this problem: <iframe class="fragment" src="/render_code/4?code=name%20is%20Sophie%0Aprint%20My%20name%20is%20name"></iframe> <aside class="notes">This code doesn't work in this level! Let the students predict the output. The problem is that if you use the variable name, you can no longer use the word name in your text. The output of this code will be 'My Sophie is Sophie'.</aside>

Fixing it with quotation marks ### Fixing it with quotation marks In this level we will fix this problem by using quotation marks. This also makes our code look more like 'real' Python code. <iframe class="fragment" src="/render_code/4?code=name%20is%20Sophie%0Aprint%20%27My%20name%20is%20%27%20name"></iframe> <aside class="notes">The computer now knows the difference between the text 'name' and the variable name. Show the students that the computer now prints 'My name is Sophie'. A student might say you could have also easily fixed this problem by giving the variable is different name. That is true, but it is an important skill in programming to show the computer different types of data and for yourself to know the difference between normal text and variables. Type quotation marks like ' or the double quotes like this ", backticks like this ` do not work!</aside>

Quotation marks with print ### Quotation marks with print Each time you use the `print` keyword you need to put the text that you want to appear on the screen in quotation marks. <iframe class="fragment" src="/render_code/4?code=print%20%27Use%20quotes%21%27"></iframe> <aside class="notes"></aside>

Quotation marks with ask ### Quotation marks with ask This also goes for the `ask` keyword. <iframe class="fragment" src="/render_code/4?code=name%20is%20ask%20%27name%20please%3F%27"></iframe> <aside class="notes"></aside>

Quotation marks and variables ### Quotation marks and variables You do not want variable names to be printed on the screen. This is why variables should be left out of the quotation marks, like this: <iframe class="fragment" src="/render_code/4?code=name%20is%20Harry%0Aprint%20%27Hello%20%27%20name"></iframe> <aside class="notes"></aside>

Quotation marks and variables ### Quotation marks and variables When variable names are used in the middle of a sentence, you have to leave the variables out of the quotation marks. The rest of the sentence however, does need quotation marks. That looks like this: <iframe class="fragment" src="/render_code/4?code=name%20is%20Harry%0Aprint%20%27Hello%20%27%20name%20%27%2C%20how%20are%20you%3F%27"></iframe> <aside class="notes"></aside>

Quotation marks and contractions ### Quotation marks and contractions Be careful! Now that you are using quotation marks, you can't use apostrophes in contractions. Please try to print a contraction like "you're" or "I'm" in the screen below and see what happens.... <iframe class="fragment" src="/render_code/4?code=print%20%27This%20won%27t%20work%27"></iframe> <aside class="notes"></aside>

Fix it! ### Fix it! If you have to use an apostrophe in your text, use double quotes to fix the problem. <iframe class="fragment" src="/render_code/4?code=print%20%22I%27m%20using%20double%20quotes%22%0Aprint%20%22It%27s%20easy%20to%20do%21%22"></iframe> <aside class="notes">It is important to start and end with the same type of quotation marks, you can't start a line with a ' and and on a " for example.</aside>

Clear ### Clear In this level you'll also learn the clear keyword. With this keyword you can wipe all the text from your output screen. Be careful that you always use a sleep keyword too. If you don't the computer will wipe all the text before you can read it! <iframe class="fragment" src="/render_code/4?code=print%20%273%27%0Aclear%0Aprint%20%272%27%0Aclear%0Aprint%20%271%27%0Aclear%0Aprint%20%27SURPRISE%21%27"></iframe> <aside class="notes">Run the code and show the students the program. You will notice that you cannot read the 3, 2, 1. Add sleep keywords before the clear keywords to fix the program.</aside>

Drawing in `color` ### Drawing in `color` Lastly, you can use `color` to make your drawings even better! <iframe class="fragment" src="/render_code/4?code=color%20blue%0Aforward%2030%0Acolor%20red%0Aforward%2030%0Acolor%20pink%0Aforward%2030%0Acolor%20yellow%0Aforward%2030"></iframe> <aside class="notes"></aside>

Debugging ### Debugging Let's debug this code! <iframe class="fragment" src="/render_code/4?code=clear%0Aprint%20What%20a%20nice%20day%20to%20go%20to%20the%20beach%21%0Aask%20%27Do%20you%20want%20to%20build%20a%20sandcastle%20or%20swim%20in%20the%20ocean%3F%27%0Aprint%20%27You%20would%20like%20to%20activity%20%27%0Aprint%20%27I%27d%20like%20to%20do%20that%20too%27%0Aprint%20%27Look%20at%20these%20beautiful%20seashells%21%27%0Acolors%20is%20%27orange%2C%20silver%2C%20white%2C%20brown%27%0Aprint%20%27I%20love%20the%20colors%20at%20random%20one%21%27%0Achoice%20is%20ask%20Which%20one%20do%20you%20like%3F"></iframe> <aside class="notes">Model how to use the debugger and the eye icon.</aside>

Ready, Set, Go! ### Ready, Set, Go! Enjoy the adventures in level 4! <aside class="notes"></aside>

Let's review! ### Let's review! What did you learn today? <aside class="notes">Ask the students to list what they've learned today.</aside>

Let's review! ### Let's review! Which adventure did you like best? Why? Which adventure did you like least? Why? <aside class="notes">Ask the students for their opinion.</aside>

Show and tell! ### Show and tell! Would anyone like to show the class a program they've made? <aside class="notes">Let some students show their work to the class.</aside>

Sneak peek into the next level... ### Sneak peek into the next level... In the next level you'll learn how to make the computer react differently to different input! <aside class="notes"></aside>