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Pilot Perspectives: Reflections on the Scratch Curriculum Guide by Alvin Kroon of Kamiak High School

After releasing the Scratch curriculum guide draft in the fall of 2011, the ScratchEd Team was interested to see how the Creative Computing curriculum was being implemented across different settings. We invited ten K-12 educators from across the U.S. to pilot the guide in their classrooms. We asked them to let us know what happened – what worked, and what didn’t. In this special ScratchEd Story series, pilot participants share their experiences and provide feedback about the curriculum guide.

We hope that these vignettes will help illustrate the range of possibilities for using the Scratch curriculum guide in K-12 settings. We encourage anyone who is using the Creative Computing curriculum to share feedback in this discussion forum

Scratch Educator:
Alvin Kroon 
School: Kamiak High School

Location: Mukilteo, Washington

Guide Usage: Seven-Week Unit (October 14 – December 2, 2011)


Our computer programming sequence consists of two courses: Introduction to Computer Graphics and AP Computer Science Java. Intro to Computer Graphics (ICG) is a semester long, 18-week exploratory programming class using three software packages: Racket, Scratch, and Google SketchUp. This year, I have 55 students in two, 50-minute sections (10 girls and 45 boys). I anticipate 25 will move on to AP Java next school year.

After seven weeks of Racket, I introduced Scratch, incorporating the 20-session Scratch curriculum guide into our six-week unit. We found the Creative Computing curriculum’s spiral of: Planning-Reflecting-Creating-Exploring to be a natural extension of Racket’s Design Recipe which consists of: Purpose statement, Expected output, Required Input, Function code, Tests and Revisions. Since our ICG students were already programming (and took the elective class to learn programming) we found the introductory ideas in the guide to be an interesting review in a new context of GUI programming. I was initially concerned that some of the ideas were too geared to the elementary level for my high school kids, but I found that we’re never too old to be young (or at least immature) again.

I ran into a few technical issues with file management. Scratch wants to save to a Drive Letter  (ie: C:\My Documents\My Projects), but our school’s network uses Path Names instead of Drives. We finally resolved the issue with Computer Services, but it presented a challenge as the Scratch files can be very large.

I’ve found that it usually takes me three years to develop and teach a topic. I know Scratch better, I’ve discovered most of the stumbling blocks that the students will encounter, and I have a better feel for teaching around those issues. By starting the year with Racket (Scheme) the students were familiar with the discipline and concepts of programming. Scratch was just a more fun way to do things and reached a much broader range of intellectual levels and learning styles. My classes were a mix of SPED, regular, and AP students as well as several autistic students. All were engaged by Scratch and worked hard and long hours on their projects. The Creative Computing curriculum has been an immense help and I plan to build my Scratch unit around it next school year.


Week 1 (Curriculum Sessions 1–4 ): Session 3’s “Learn to express a complex activity using a sequence of simple instructions” was most helpful. It was very helpful to physically follow very specific commands one thing at a time. Our computer lab has six rows of five workstations, so we worked in “Row Teams.”

Week 2 (Curriculum Guide Sessions 5 & 6): We had already done the art project in the Racket language, creating animated collages of various graphic shapes. Scratch allowed us to expand these ideas with its parallel and event-driven tools. Adding the interactivity of the “broadcast” and “when I receive” blocks created a lot of interest. We explored the Six-Word Stories by students typing them in Word and then doing a Gallery Walk where other students commented on each other’s stories.

Week 3 (Curriculum Guide Sessions 7–9):  I used the Stories and Scenes handouts for a “Top Ten Movies” project. Importing and properly sizing .jpg files was a big issue. We used Photoshop’s “Save for Web and Devices” to shrink the .jpg files to usable sizes. The Debug It! handouts were great – we needed more of them. I used them as warm-ups at the start of the class. Students would produce at least three different solutions for each debugging challenge, and this lead into a great “what constitutes the best solution” discussion. I supplemented the debugging challenges with the Block Cat and Cat Tree lessons (attached below). These are Algebra lessons and should work with middle school and high school students.

Week 4-5 (Curriculum Guide Sessions 10–13): We started planning for final projects. Students were given the choice of a game, a children’s book, a fantasy story or an approved choice. High school boys like First Person Shooter games, but they had to be PG in language, graphics and violence (see examples below). The Project Planner handout and storyboard sketches were required before they could work on their project.

Final project presentations: Everyone moved to the front three rows and I loaded each Scratch project at my workstation and the students started their presentations. I was astonished at the sophistication and deep thinking that went into their projects. Most spent at least 35–40 hours on their projects – 15 hours in the classroom and the rest at home. Every student got a sincere round of applause. The most frequent comment was that this was a lot more work than they thought it would be.

I opted to implement the design journals as a digital notebook. The students downloaded a .doc file that I posted on the network server and made entries as they completed an activity. Then they uploaded their files to a digital Dropbox so I could review their work from my desktop.

The following are students’ responses to the reflection prompts: Now what? What are you most proud of about your project? What would you change? What do you want to create next?

“I am most proud of the hand following the mouse cursor. I would make A LOT more levels. A game where things follow the mouse around the screen and you have to dodge them because it would be a lot more fun.”

“I’m proud that I did the project all on my own. I was able to get it to move and work exactly the way that I wanted to! If I changed it I would make the levels a little bit harder and have something chase you around like in the real Pacman game. I want to create a sprite that will move around to try and catch the Pacman.”

“I’m proud about the whole thing. The sprites are done quite nicely, and the physics of our game are also very nice. The only thing I would change would be the size of the sprite so we could make bigger stages. I really feel like making a racing project because I would love to incorporate some sort of physics in it.”

“We are proud that we were able to get the timing perfect for our project because we spent a large portion of our time on the timing. We even spent some time writing out our script on paper to visually see the entire story. We would like to make our story into a game where the audience can be more active with it. That way, the audience is more engaged in our story.”

“I am pleased with my project because I used my creativity and put together a decent children’s story. Next time I would make the story more interesting because it’s important to keep the child interested in what they are reading. Next I would want to create another game now that I am more familiar with Scratch and will be able to make everything flow together. Before I gave up and didn’t try to improve my Scratch skills because it all confused me. But I stayed focused, took my time, and gathered enough skills to put something else together.”

1) Don’t be nervous about your students knowing more than you – in computer classes there’s ALWAYS someone who knows (or thinks they know) more than you.  Leverage their knowledge to the class’s advantage.

2) Take time to practice the lessons in advance. Don’t be afraid to ask for help – that’s one of the primary roles of this group.

3) Always prepare more materials than you plan to use – some lessons go very quickly.

4) Build a good relationship with your network/tech people – cookies, candy, thank-you-notes help.  Be sure to test network access to Scratch websites – it’s very frustrating to find a site you planned to use blocked with District safety controls.  If this happens, ask your network admins to unblock legitimate sites before you try to teach that lesson.

5) If you have older computers, minimize the use of imported graphics, especially copy and paste bit maps – the files can get huge very quickly.

6) Enjoy the creativity and joy of your students. 

Alvin Kroon



Contact me at:  I'm more than happy to talk with you.



Sarah Johnson

Would love to talk with you about this project.  I'm currently teaching a one-semester on-line class using Racket as the intro to computer science to my high school students.  I'd love to incorporate Scratch but think that I would like to do it first, rather than afterward.  Please let me know if we might talk further.