‘16-‘17 General Discussion for Lesson 5.18


Use this thread to discuss your questions and comments about how to run the lesson.


First of all, I LOVE seeing all the cool things students are doing in App Lab! Wow! It is amazing to see students’ creativity take over!

Now, for the writing part, my students noticed that the “difficulty” they ran into (in 2b), probably had to do with their most “complex algorithm” (in 2c) - so they found themselves writing about the same thing in 2b and 2c. Furthermore, their algorithm was probably part of a function that they were going to use as abstraction (thus also writing about the same thing in 2d).

I am hoping that it is ok for students to write about the same thing 3 times in a row but just shift the focus of how they talk about it.

  1. For 2b, they should describe what the difficulty they ran into was, and how they fixed it

  2. For 2c they should write about how their algorithm works (get into the nitty-gritty of how it functions) and how it uses other algorithms

  3. For 2d they should focus on how breaking these algorithms into functions and calling the functions as they did made their code less complex.

How are other people thinking about this?


Hi all,

I thought I would share some apps my students did for this project. There were some really creative ones!

I am thinking next year I am going to do a few more group projects and see how students might implement them together. Something like “Hangman” might be good for that since everyone knows how to play, it seems really simple, but there is a lot to take into account. What are some other unique/interesting apps students designed for your projects?


this is awesome! thanks for sharing, @kaitie_o_bryan!


@kaitie_o_bryan These are cool! I like the weight lifting one… obviously. I looked like two boys may have made it. As a girl weight lifter I would love the option to pick the girls weight bar (15kg or ~35lbs) and have the app work for me too :slight_smile: Thought maybe some user feedback would be fun!


Good point! I will pass it on!


These are super cool. My students in my Java Programming class were amused by the sounds coming from my iPad. I previewed them in class and made a recruitment pitch for AP CSP.
Thanks for sharing.


Hello - this is my first go-around with Code.org APCSP so I apologize if I’m not doing this correctly - my students want to access the phone’s camera or use a function like “isShaken()” (this was something we could do in appInventor last year) … just wondering if there is a way to access the phone’s sensors or camera or texting/calling features from within App Lab?
Thank you so much!!


I had a question about question 2b. When students describe the algorithm, they would be describing a function. I wanted to make sure I was clear that describing an onEvent action is not a function, but an event and therefore not an algorithm. Is that true?


After doing some research on Events, I think I answered my own question. An event is not an algorithm since it calls an algorithm (function or functions) based on a system event. Therefore, a student can’t discuss an event as an algorithm, but they can discuss the function that has been called from the event. Any comments?


Yes I agree. I will ask my students to focus on functions they create.


Does anyone know the code in App Lab to round a number to the nearest tenth?


Hi @jjohnson,

I think the only rounding function that is included in App Labs tool box for rounding is Math.round (https://docs.code.org/applab/mathRound/) . However it looks like you can use that function to get a number rounded to the nearest tenth. Check out this stack overflow about it - http://stackoverflow.com/questions/7342957/how-do-you-round-to-1-decimal-place-in-javascript .




This works great!

var x = Math.round(15.2);
var y = Math.round(23.5);
var z = Math.round(-7.8);

var x = Math.round(15.2444556 * 10)/10;

var y = Math.round(23.55656 * 100)/100;

var z = Math.round(-7.8459988 * 1000)/ 1000;


A student would like his app to contain a scrolling screen. Is this possible in App Lab? I’ve been looking through the API and nothing is jumping out at me for this possibility. (I couldn’t get createCanvas to work.)


I don’t think that feature is available. I have posed the question to code.org team and they will correct me if I am wrong.


@twatson you can’t scroll down an actual screen but if you need longer blocks of text content the “text area” will become scrollable once the content inside of it is larger than can be displayed. This may help solve for some of the situations you’re thinking about.

The canvas element isn’t scrollable unfortunately. If you have more questions about it though let us know and we’ll be happy to help!