Pilot - U1L07 - Storage


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I taught this lesson to my students in my Girls Who Code club a few days ago and the results were sort of mixed.

A little background on the classroom:
We range about 20-30 girls a class, grades 6th-10th, most have no prior programming experience or have only worked in Scratch (although we have about 5 or 7 returning students from last year who use JavaScript and Python).

There was a 15-ish minute discussion before we started that was about information, what things a computer might need to store, the inputs and the outputs of a computer and what things a computer might need to process. The girls completed these activities in groups of 2-3.

This activity was not popular among the girls. Some of the older students (8th and 9th grade) enjoyed the activity, but the younger ones (6th-8th) really didn’t like this one.

Main complaints from students:
The middle card challenge was too hard/confusing. A lot of girls thought having 4 challenges was unnecessary.

“Too much writing”, students didn’t like writing their algorithms out by hand. They asked if they could type it instead, or just talk out their algorithm with the class.

Too tedious/took too long as a whole.

Instructor notes:
Even after having the activity demonstrated to them, a few girls still found it hard to understand what they were supposed to do.

My co-instructor suggested having a constraint on how many save spots can be used: “Going ‘Look at all those in safe spaces and tell which one is the biggest’ is a primitive operation not supported in most computers”

Are jokers supposed to be taken out of the deck? The instructions don’t say.

Overall: maybe shorten this activity?


12 students, 9-12th Grades with little experience in CS

U1L07 Alternate - Storage and Processing

I did this lesson because in the small time I gave the students to work on the final project (80 minute blocks and it was the last 20 or so of the Unit 1, Lesson 8), I had one group ask about the “processing part” and then it was brought up in a weekly call, so I tried this. This lesson used the cards again, and my students were excited about that because, as mentioned in a previous post, they really enjoyed the hands on and competitiveness of it. Fortunately the students had an idea of what the final project was so they knew how this lesson on storage and processing could be applied - as a modification for myself I’ll probably try to weave parts of the final project into the earlier lessons so they know where everything is going. I only did a 2 second demonstration because didn’t want to define how many storage places were needed, just showed them the process.
Most of my students quickly caught onto the smallest and largest cards, then the second largest threw them slightly - but they struggled (in a good way) with the middle card, as they should. It was interesting watching them go to the problem solving process unprompted (although I remind them of it at the beginning of every lesson). It was a good challenging exercise that might be too difficult for younger ages considering it was a challenge for over half of my class. This took about 50 minutes (albeit there was a brief conversation about shuffling and how only 3 kids knew how to shuffle the “traditional way” which made me question the “traditional way” but that was a tangent, as is this sentence…) and then 20 minutes spent looking at the Final Project again.
After the two lessons on sorting and searching, I couldn’t resist but should some of my favorite videos on Youtube of the visual sorting algorithms (here is a channel, but more are available). I love introducing students to them, and watching them a few times to have them try to explain the process. I’ve been doing this for a number of years and the recent introduction of the half speed and quarter speed has been really helpful to show students the slowed process. After each one I had them compare and contrast the method they used to see if it’s similar to the method we watched.


Thanks for sharing your experiences. It sounds like the kids had just enough challenge. I like the idea of making sure that the kids have the context for how to apply the lessons on storage and processing.


I teach at a high school in SLC, Utah. My class is very diverse in that we have multiple languages in the class, English is not the native language of 95% of my students, I have pretty close to 50/50 boy, girl ratio and the class is a good representation of students from the entire school ranging from grades 9-12. Our class period is 90 minutes every other day.

Definitely use the video GT made as a resource for yourself to understand the activity and for students to see someone trying it out.

Be thoughtful with pairing students so that you have students who have played with cards before an know their value - otherwise, establish what each card is worth as you do the activity.

It is ok to let the students struggle a little as they figure out the storage spots. This is where you can walk around and gain some understanding about students thinking process of computers, storage, input/output and if necessary do a great wrap up of what concepts were covered and where you saw that in the curriculum.


@nicole Good teaching tip about making sure students know the “value” of cards. We will add that to the lesson in the future!


I teach 7th graders in a suburban, mostly white, English speaking middle school.

I taught this lesson on the heels of the original lesson 7. GT had gone over it in our weekly call, which really helped me to better understand the lesson goal and how the activities helped to get us there. I did a short demonstration of the activity and I made a couple of card value cheat sheets for those students with little experience with playing cards and made sure that everyone considered aces high so there was some continuity. I told my students that they were essentially working independently to do the challenges, but that they had a partner to work through the algorithms. I really had to push my students to write thorough algorithms. This irritated them, but they did it. :slight_smile:
My students grasped challenges 1 & 2 fairly quickly, but did struggle with challenge 3 & 4. It was good to watch their thinking. Many times students would have an “AHA” moment and call me over just to tell me they had figured it out when really they hadn’t. They had only gotten lucky and when asked to reproduce their results they couldn’t. This was a great lesson in persistence. I eventually had to coach a few students through challenge 4 because they were simply running out of time and problem solving patience. I didn’t want them to get lost in the single challenge and lose the point of the overall lesson. All in all, I would use this activity again with very few changes.


Hi Elizabeth,

Great idea for the cheat sheets for the card values. I’m so glad your kids are getting that persistence. What changes would you make for next time?


The activity was successful introducing the idea of running memory or temporary storage.

My students pointed out to me that we were breaking the rules by handling more than one card at the time.
Our conversation let us to make the possible solution of stacking the cards instead of eliminating them, which later on I found out is a misconception.
In the future I will reword the rules so that it is emphasized that the safe spots can only contain one card (rule 7) and give less importance to how the card gets there (rules 1 and 2)


Excellent point @pedro_uribe we’ll be updating the activity to reflect those changes!