Students will be able to...
- Build custom blocks that take arguments.
- Do Now 3.3
- 3.3 slide deck
- Lab 3.3 - Let me check my calendar (docx) (pdf)
- Arguments example
- Unit 3 tips
- https://youtu.be/ZLxql1kLvCw
- Video quiz: See Additional Curriculum Materials accessed from the TEALS Dashboard.
| Duration | Description |
|---|---|
| 5 minutes | Welcome, attendance, bell work, announcements |
| 15 minutes | Lecture and introduce activity |
| 20 minutes | Custom block argument activity |
| 15 minutes | Debrief and wrap-up |
Introduce block arguments
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Define Arguments: An argument is any area in a block that accepts user input, or another block. It could be a Boolean Block or a value placed inside of a variable or block.
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Ask students to speculate on risks of relying on variables instead of arguments.
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Variables could be changed by a script other than the custom block, variable names could be changed causing errors, etc.
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Emphasize importance of custom blocks being self-contained.
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Custom blocks should continue to function correctly independent of any other changes in the script.
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Custom blocks should work correctly anywhere in the script and not require specific setup or cleanup.
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Point out how complicated a script would be if blocks like move 10 steps required setting a variable with a specific name to work.
Demonstrate declaration and usage of arguments
Point out that arguments are very similar to variables, except their values come outside the block.
Explain argument types.
- Only discuss text, numbers, and Booleans.
- Other types can be mentioned, but won't be used in the course.
Ask students to describe why restricting types is important.
- Point out that arguments are passed by value.
- Specifically, changing the value of an argument inside a custom block will typically NOT change the value at the call site.
- Basic argument in pen category.
- Pass by value example in "Variables" category.
Students should complete the Let Me Check My Calendar activity individually or in pairs.
- This lab consists of a series of independent custom blocks. The blocks need not necessarily be completed in the order given, but are roughly in order of difficulty.
The bonus requires implementing a fairly complex formula.
- Ask a different student to provide their solution to each part.
- If time allows, discuss multiple solutions to each part.
- Emphasize differences and encourage discussion about advantages and disadvantages.
- Point out corner cases and cases where typed arguments are particularly helpful.
- For example, avoiding try to find out whether "bubblegum" is a leap year.
- Part 3.4 is a fairly complex formula and should be a challenge for advanced students.
- Struggling students should focus on section 1. The problems in section 2 represent more complex algorithms, but not necessarily any more difficult usage of arguments.