D. Nixon: CS 12 > Week 2

Home (CS 12) | Assignments | Tutorials | Examples | Quizzes & Exam | Other Info | Chat

Computer Science 12


Week 2




Sunday, February 9, 2020



Assignment 2 (see distinct due dates for each part)

  1. PowerPoint slideshow, part 1 (due Sunday, February 23, 2020)
  2. Excel assignment (due Sunday, February 16, 2020, before class)
  3. Scratch assignment (due Sunday, February 16, 2020, before class)
  4. Problem-solving paper, part 1 (due Sunday, March 1, 2020; preliminary email due ASAP THIS WEEK)

  1. PowerPoint slideshow, part 1 (due Sunday, February 23, 2020):
  2. Create a series of 5 to 10 PowerPoint slides in which you (1) compare each of at least two PowerPoint drawing/graphics tools to its nearest corresponding Scratch drawing/paint tool, and (2) very briefly compare PowerPoint as a whole, in a general way, to Scratch as a whole. (PowerPoint and Scratch are very different kinds of programs but have some capabilities in common.)

    For each type of paint/drawing tool you discuss, indicate whether PowerPoint and/or Scratch has (a) a raster (a.k.a. bitmap) version of the tool, (b) a vector version of the tool, or (c) both. Find at least two other points of comparison between PowerPoint's and Scratch's variants of the tools as well.

    Also, note that PowerPoint has both "drawing" tools and "ink" tools. What are the key differences between these two categories of tools? ("Drawing" tools can be used on a desktop or laptop with a keyboard and mouse, whereas "ink" tools are intended to be used with a touchscreen on a tablet.) Your slideshow should be primarily about "drawing" tools, NOT "ink" tools, although, if there happen to be "ink" tools similar to the particular "drawing" tools you have chosen, your slide show should briefly mention the relevant "ink" tools too, clearly distinguishing each "ink" tool from its corresponding "drawing" tool.

    At least one (and preferably more than one) of the PowerPoint drawing tools you discuss must be visibly used (as well as described and/or depicted) within your PowerPoint presentation itself. At least one of your slides must contain a drawing created using one or more of PowerPoint's drawing tools. (A very simple drawing will suffice; it doesn't need to be anything fancy.)

    (Because this course requires you to use a desktop or laptop, but not a tablet, you are NOT required to learn how to USE the "ink" tools, but only to be aware of their existence.)

    Do NOT include any animation features in Part 1 of your slideshow. You'll be asked to deal with animation later, in Part 2.

    Note that a PowerPoint slideshow is not an essay. Your slides should be designed to serve as appropriate visual aids if you were to give a brief lecture about the paint/drawing tools of PowerPoint and Scratch. Your slides should be clear but brief, with just enough information to help your hypothetical audience take good notes. Your slides should NOT spell out all the details, but should focus on the main points. It is recommended that each of your slides (except for the final credits slide) contain one of the following: (1) a brief introductory sentence followed by a list of bullet points, (2) a table (very useful when summarizing comparisons), and (3) a picture with a caption, where the picture may be either one of your own drawings or an imported graphics file. Your slideshow should include all three of these types of slides.

    Nevertheless, your slideshow MUST still have the following in common with an academic paper: The last slide must be an acknowledgments/credits page. If, on any of your slides, you copy and paste any text from the web, be sure to identify it as a quote (e.g. by putting quote marks around it) and then identify your source, in two places: (1) briefly, on the page where the quote is (e.g. as a fine-print footnote), and then (2) with a more complete bibliographic listing on the credits slide. Likewise, identify the source of any graphics you use. Not doing so is plagiarism. (See also CUNY's Academic Integrity Policy.) Your credits slide must include a small-print list of all tutorial material from which you copied either text or graphics. You must list at least two tutorials, with full bibliographic data, including their URLs if they are on the web. Furthermore, ALL graphics must be credited, even if you drew or photographed them yourself, in which case they should be credited to yourself, e.g. your credits slide may contain a sentence like: "Unless otherwise specified, all graphics are copyright ©" 2020 [YOUR NAME]. All rights reserved."

    Give your PowerPoint presentation a filename like the following:

    As always, replace "last" and "first" with your own actual first and last name. Submit the file as an attachment to an email with the following subject line:

    PowerPoint slideshow Part 1, LastName FirstName

    where "LastName" and "FirstName" must be replaced by your own last name and and first name, respectively.

    Warning:  You must follow the above submission instructions EXACTLY in order for your slideshow to be graded at all. If you do not use the correct filename, or if you do not use the correct subject line, then your slideshow will not be graded at all. These rules are necessary in order for me to keep track of your homework emails.

  3. Excel assignment (due before our next class):
  4. In this and all future Excel assignments, every required quantity that can be computed from other data in the spreadsheet must be computed by the spreadsheet itself via a formula in the appropriate cell, using cell references. Moreover, if a formula needs to appear in every cell in a column of a table, the formula must be one that you can type just once, in the first data row of the table, and then drag it down the column.

    Below are the first parts of what will be two ongoing Excel projects, a grade roster and an invoice. Because they will be continued in next week's class, you must submit both of these before next week's class in order to receive credit for them at all.

    1. Roster:  Making believe you're a teacher, create an Excel spreadsheet with columns as follows: (1) a list of names, with one column for the last name and another column for the first name; (2) five columns of quiz scores, (3) two columns of results to be computed from quiz scores, (4) two columns of in-class exam scores, and (5) the final exam score. The two columns of results computed from the quiz scores must be (a) the average quiz score and (b) the average with lowest score dropped.
    2. (See this tutorial on how to compute a quiz average with lowest score dropped. Also, note that the column heading for the quiz average with lowest score dropped will look very ugly unless you use line breaks inside the cell. For info on now to do that, see this week's Excel tutorials.)

      Make rows for at least five students. The names of your imaginary students, and the quiz scores, will be left to your imagination. Just don't copy them from another student. Make up a unique set of at least five names (not used by other Computer Science 12 students). The quiz scores should range between 0 to 10, while the exam scores should range between 0 and 100.

      Above the scores, there must be a row for column headings. The column headings for the quizzes should be: Quiz 1, Quiz 2, Quiz 3, Quiz 4, and Quiz 5. (Don't type all five of these quiz headings by hand. Type just two of them, then generate the rest by dragging across the row.) The column headings for the exams should be: Exam 1, Exam 2, and Final Exam.

      Save your Excel spreadsheet with a filename having the following format:

      • last-first-roster-2.xlsx

      where "last" and "first" should be replaced by your own last name and and first name, respectively.

      Then, in between the quiz scores and the exam scores, insert two columns for calculated results involving the quiz scores. The first of these should be a column for the average quiz score. The second of these should be a column which computes an average of quiz scores with the lowest grade dropped. (Hint: Use a formula involving the SUM, COUNT, and MIN functions, not the AVERAGE function.) Save the file again when finished.

    3. Invoice:  In a separate file, write an invoice for goods ordered from a store. The invoice should have columns for product name, per-unit price, quantity ordered, and total price. There should be rows for at least four products. Underneath the last row, below the total price column there should cells (with identifying text in cells to the left of them) for subtotal, tax, and then total (one cell for each of these). The tax should be computed from the tax rate, which should be placed in a separate cell somewhere outside your main table.
    4. All columns should have clear headings. And, somewhere above the headings, there should be cells for the store's name, the date, and the customer's name and address. Use two or more merged cells for the store's name. (See this week's Excel tutorials.) Likewise use two or more merged cells for the customer's name and for each line of the customer's address, so that these will display nicely, and use an appropriate heading format for the store's name. Put your own name and email address in appropriately merged cells at the bottom.

      The invoice should have a filename with the following format:

      • last-first-invoice-2.xlsx

      where "last" and "first" should be replaced by your own last and first name.

      Your invoice must be unique, containing a store name, product names, and prices different from those in files submitted by other students in Computer Science 12.

    Submit BOTH of the above files via email by no later than the beginning of our next class, and make sure you also have access to the files during lab on that day. The two Excel files must be sumitted as file attachements to a single email message. Please submit both at once, NOT in two separate email messages. The email message must be sent to:

    cs12-hw@nyclocal.net

    and must have a subject line like the following:

    HW 2 Excel, LastName FirstName

    where "LastName" and "FirstName" should be replaced by your own last name and and first name, respectively.

    We will use this week's Excel files again in future exercises both in lab and in homework. When a homework assignment is built upon in the very next lab session, as is the case for this one, the deadline is absolute; it cannot be submitted late. In case your email happens to be down during class, you should try to submit the files at least two hours earlier than the absolute deadline, and you must also have access to the files during class by some other means too, such as a flash drive or emailing them to yourself at a separate address.

    Warning:  You must follow the homework submission instructions EXACTLY in order for your homework to be graded at all. If you do not use the correct filenames, or if you do not use the correct subject line, or if you submit the files attached to separate email messages rather than as two attachments to just one email message, then your homework will not be graded at all. These rules are necessary in order for me to keep track of your homework emails.

  5. Scratch assignment (due before our next class):
  6. IMPORTANT NOTE:  We are still using Scratch version 2 this semester. The latest version of Scratch is Scratch 3, which came out only in January 2020. We have not yet updated our assignments and tutorial material to be compatible with Scratch version 3. Furthermore, Scratch 3 itself appears to be somewhat buggy (as new major software versions often are) and is not yet accompanied by adequate tutorial material. Therefore, do NOT use Scratch version 3, which is incompatible with Scratch version 2.

    If you already installed Scratch 3, please uninstall it as follows, to ensure that it does not interfere with Scratch 2:

    1. Open the Windows Start menu.
    2. Right click on the scratch-desktop application in the Start menu.
    3. Select uninstall.
    4. When the unistaller window opens, make sure that "scratch-desktop" is selected in the window and then click on "unistall".

    1. Preliminary practice:  Open Scratch. Go through the third of the built-in tutorials, "Animate A Name." If you are doing this in class, skip the parts involving sound for now. (Do them later, when you go through the tutorial again at home.) Unfortunately, the tutorial is not 100% clear and has some steps missing. See Notes on the "Animate A Name" tutorial for clarification of various issues. When you are finished going through the tutorial, don't "share" your work, but instead save the file. (Use whatever filename you like, since you won't be submitting this version.)
    2. Note that we've now worked with two ways of creating a new "sprite" in Scratch: (1) choosing a sprite from Scratch's built-in sprite library and (2) using Scratch's art tools to "paint" your own totally new sprite. Below is a cropped screenshot (taken by Aryeh Friedman) of the Scratch "New Sprite" icons, each for a different way of creating a new sprite.

      Scratch icons for creating a new sprite.

      In Scratch, hover your mouse cursor over each of these four icons to see all the ways that a sprite can be created.

      Now spend some time experimenting with all of Scratch's drawing tools, both "Bitmap" and "Vector" modes. Note that, in "Bitmap" mode, if you create a small image and then select it and make it a lot bigger, the image will pixelize, whereas this does not happen with images created in "Vector" mode. More generally, observe that "Bitmap" mode has some capabilities that "Vector" mode does not, and vice versa.

    3. Full name project:  Select "New" in Scratch's file menu to create a new Scratch project. Using the drawing tools, including one or both "text" tools, create two sprites, one for your first name and one for your last name. Do NOT make one sprite for each letter as you did in the "Animate A Name" tutorial. Instead, one sprite should contain all the letters of your first name and another sprite should contain all the letters of your last name. However, within each sprite, you should vary the appearance of the letters, e.g. by making them different colors and by creating some of the letters using the "text" tools but creating others using other drawing tools.
    4. Note that each script has an icon that you can use to select it and thereby bring it up on the canvas.

      Using techniques similar to what you learned in the "Animate A Name" tutorial, give the sprite containing your first name a script that, when the green flag is clicked, will make your first name move around the screen for a few seconds, ending up in its original position. Give the sprite containing your last name a script that will make it change colors when the the space bar is pressed.

      Save this project with a filename in the following format:

      • last-first-fullname.sb2

      replacing "last" and "first" with your own actual last and first names.

    5. The "Animate A Name" tutorial again (complete with sounds):  At home (NOT in the classroom) go through the "Animate A Name" tutorial again, creating a project as instructed, including the sounds this time. (Again, see Notes on the "Animate A Name" tutorial for clarification of various issues.) The name you use should be your own first or last name.
    6. When finished, do not "Share" your project, but, instead, save it with a filename in the following format:

      • last-first-animate-name.sb2

      replacing "last" and "first" with your own actual last and first names.

    Submit BOTH of the above files via email by no later than the beginning of our next class, and make sure you also have access to the files during lab on that day. The two Scratch files must be sumitted as file attachements to a single email message. Please submit both at once, NOT in two separate email messages. The email message must have a subject line like the following:

    HW 2 Scratch, LastName FirstName

    where "LastName" and "FirstName" should be replaced by your own last name and and first name, respectively.

    Warning:  You must follow the homework submission instructions EXACTLY in order for your homework to be graded at all. If you do not use the correct filenames, or if you do not use the correct subject line, or if you submit the files attached to separate email messages rather than as two attachments to just one email message, then your homework will not be graded at all. These rules are necessary in order for me to keep track of your homework emails.

  7. Problem-solving paper, part 1 (due Sunday, March 1, 2020; preliminary email due ASAP THIS WEEK):
  8. If you have not done so already, choose a problem relevant to your life or interests that can be solved using an Excel spreadsheet. If you expect to have difficulty thinking of such a problem, you may stay after class to brainstorm about it. Once you have chosen your problem, send me email about it ASAP for approval. Your email must have a SUBJECT line like "HW 1 problem-solving LastName FirstName", replacing "LastName" and "FirstName" with your own actual last and first names.

    Then, once your problem is approved, please begin work on the paper itself as soon as possible. As explained in Assignment 1, Part 1 of your paper should discuss the process of figuring out how to solve your problem.

    If possible, divide your problem into several smaller problems and figure out how to solve each sub-problem separately. If you can do this, your paper can discuss how you divided the problem and how you solved each distinct part and then put the parts together into your solution of the original problem. (A simple example of this technique can be found in the "jet ski" problem in the video on this page: Solving Real-Life Problems in Excel on the GCF Learn Free site.) If a clean division of your problem into distinct parts is not possible, or at least not easy, then figure out how to solve several similar but simpler problems (as exemplified in Excel problem-solving example: Quiz average with lowest score dropped), as a way to gain insight into your original problem. Your paper can then discuss both the similarities and the differences between your original problem and the simpler problems.

    In either case, you are likely to encounter a few pitfalls along the way. Your paper should discuss these sources of error and confusion and how you found and fixed your errors. For some hints on how to track down errors, see Double-Check Your Formulas on the GCF Learn Free site.

    If you used any tutorial material, be sure to credit your sources in the paper.

    You may also copy and paste excerpts from your spreadsheet into the paper, as illustrations. If you do that, give each such excerpt an appropriate caption in your paper, indicating its significance.

    Part 1 of your paper may be anywhere between 2 and 5 whole pages long, double-spaced. To make it easier to read, it should be organized into sections with headings, where each section is no longer than one full page but no shorter than half a page.

    Submit BOTH your paper (Part 1), as a Microsoft Word document, and the spreadsheet in which you solved your problem, as separate files, together in one email message, by no later than Sunday, March 1, 2020. Your paper must have a filename with the following format:

    replacing "last" and "first" with your own actual last and first names. The accomanying spreadsheet must have a filename with the following format:

    again replacing "last" and "first" with your own actual last and first names. Submit both files together in a single email message with a subject line like the following:

    Paper part 1, LastName FirstName

    where "LastName" and "FirstName" should be replaced by your own last name and and first name, respectively.

    Warning:  You must follow the above submission instructions EXACTLY in order for your paper to be graded at all. If you do not use the correct filenames, or if you do not use the correct subject line, or if you submit the files attached to separate email messages rather than as two attachments to just one email message, then your homework will not be graded at all. These rules are necessary in order for me to keep track of your homework emails.


To all information for Week 2  |  To all homework assignments



Tutorials on Excel

On Excel functions in general, and specifically the SUM, AVERAGE, COUNT, COUNTA, MIN, MAX, and MEDIAN functions:

Line breaks in cells:

How to merge cells:

It is recommended that you also use Excel's Help feature to get more information on all of the above.

See also the Excel tutorials listed for Week 1.


To all information for Week 2  |  To all tutorials about Excel



Tutorials on Scratch


To all information for Week 2  |  To all tutorials about programming (very basic intro)



Tutorials on PowerPoint

See last week's tutorials on PowerPoint.


To all information for Week 2  |  To all tutorials about PowerPoint



Tutorials on operating systems: Windows filename extensions

Filename extensions in Windows:  This week's tutorials about graphics files mention some graphics filename extensions. However, Windows hides filename extensions by default. So that you can see filename extensions in Windows, see:


To all information for Week 2  |  To all tutorials about computer basics, operating systems, and non-web Internet



Tutorials on miscellaneous topics: Vector vs. raster graphics

Vector graphics (a.k.a. "object-oriented" graphics) vs. raster graphics (a.k.a. bitmap graphics or pixel-based graphics):


To all information for Week 2  |  To all tutorials about miscellaneous topics

D. Nixon: CS 12 > Week 2