Friday, October 28, 2011

Simon Says - Recursion!

Spotted this today - they are reissuing Simon Says. The interface reminds me a lot of the Siftables that were designed at MIT. 

Not only are these just plain awesome, the old Simon Says game is a great way t teach the concept of recursion. Can you say QUEUE?


 

Thursday, October 27, 2011

Cups and Strings - follow up

(This is part 2 - Read about Part 1 here)
This activity went great today.We used cups instead of cans - worked perfectly. They worked in group of four. Each group got string, two cups, scissors and a copy of the Morse code chart. They were asked to first send voice messages, then use Morse code to send a message. Each group reflected on how they agreed to communicate dots and dashes and how they knoew the message arrived correctly. They were then asked if they had to use this method to transmit a messgage back to town (we're in the sticks) what would they do?


This may seem like a simple and silly activity, but it really ties into seeral things we will be covering the next few weeks. First, all data is sent over the Internet using some form of encoding. For this to work you have to agree ahead of time on a set of protocols. Their communication with the cups required a dedicated line, the string. One of the major developments that led to the Internet was Leonard Kleinrock's ideas about dividing messages into smaller packets which moved us past the need for dedicated lines. In networking and other areas there are things we can do numerically to check if a message arrives correctly. The list goes on.

A fun side effect was they had to deal with interference on their lines. As other students moved theough the halls we had various "interruptions in service". One involved a kid licking the string, no idea why.

While I hope the Internet is safe from licking, it is certainly at risk of natural and man-made interrruptions.

I had several students stop and ask what we were doing, and it was a hoot to hear my kids explain how awesome computer science is. They were the perfect ambasadors. In a moment so perfect I couldn't have scripted it if I tried one of my students explaind to his friend we ran into that "everyone should know this stuff, it's important".

The groups really experimented with this. One group created a three-way syste. Interesting fact, the cups have to be nearly equidistant for a message to transmit to all three cups. My favorite was the group that used Pythagorean theorem to find the length of their string.

Wednesday, October 26, 2011

Cans and String: The Internet Unplugged

I am still gathering materials for the CS Principles course. Every time I think I am caught up I find something new.

Today while reading over the blog by Harry Lewis , author of Blown to Bits, I found a book that is exactly what we are going over right now.

On my shopping list: D is for Digital by Brian Kernighan. He teaches at Princeton. Here is the course website: Princeton site for CS 109

We are in the middle of Unit 2-The Internet Unplugged. We've done HTML, as an example of abstraction and creating digital artifacts. We'll be adding CSS next week. right now we are talking about the physical structure of the Internet. I honestly thought this lesson would be a bit dull, but the students really had a lot of questions. I try to end each block with an "exit ticket". Last class they had to tell me one thing they had learned new and one thing they were curious to learn. This helps me steer where we are going.

It is amazing how little they really know about the Internet...it has been omnipresent since they were little, so very few of them have ever really looked at the how and why behind it all. To me it is foundational for technological literacy.

I am so glad we started with binary this year. Honestly it was a stall tactic-I had planned on doing it when we got to number calculations, but I had a few days to fill in Sept so we did binary, octal and hex. It had turned out to be perfect- so much of what we have done has related back to that lesson. Tomorrow we talk about IP addresses.

Tonight I am forcing my own children to eat a buffet of canned foods. Fortunately they like tomato soup. We're doing the "Two Cans and a String" game tomorrow and I am a bit short on cans. My challenge for the students is to discover how long a piece of string can be before the message breaks down. My plan is to use this an introduction to error checking - how do you KNOW the message you get is correct? I think it will also help with the idea of packets.

I have also been reading The Internet of Elsewhere. I am still reading the chapter on Korea. It includes a great description of the beginning of packets on the ARPANET. I like that it makes the connection that before packets information had to be sent in one long dedicated connection, like a phone call. I am hoping that our Cans and Strings activity will also help drive this point home.

Monday, October 17, 2011

University of Washington APCS Materials

AP Computer Science Materials This site is from a summer workshop they run for APS teachers. It includes several good sample assignemnts from their CSE142 course.

Thursday, October 6, 2011

Cybersecurity

Found this class site from Stanford with some good information on cybersecurity. Only the first few lessons are useful at our level, but it is good stuff.

Saturday, October 1, 2011

CS Ed Week

CS Ed Week

Computer Science Education Week (CSEdWeek) – December 4-10, 2011 – is a call to action to share information and offer activities that will advocate for computing and elevate computer science education for students at all levels. Everyone can participate!

NCWIT - Award for Aspirations in Computing - Virginia Affiliate

High school young women in your community are invited to apply for the NCWIT Award for Aspirations in Computing - Virginia Affiliate. Please help us publicize this opportunity and encourage candidates to apply.


  • NCWIT Aspirations Award



  • NCWIT


  • What is the award? The NCWIT Award for Aspirations in Computing recognizes young women at the high-school level for their computing-related achievements and interests. Winners are recognized at an award event here in the community. All applicants will also be considered for the National award.


    Why is the award important? By generating visibility for technical young women, the NCWIT Award for Aspirations in Computing encourages continued interest in computing, increases awareness of the gender gap in computing and IT, and emphasizes at a personal level the importance of women's participation in computing.

    What is my role? We are asking everyone to help promote the Award and encourage girls with accomplishments and aspirations in computing to apply. Please broadcast this opportunity among your networks and copy and distribute the attached Poster and Info Sheet to likely candidates. The Info Sheet describes eligibility criteria and supplies everything girls need to apply.

    What is the application process? Please duplicate and distribute the poster and flyer and direct girls to http://www.aspirationsaward.org. Detailed instructions and eligibility information are found online.

    What is the deadline? Please notify girls of this opportunity right away. Online applications opened September 15, 2011 and must be submitted and endorsed by October 31, 2011.

    Snappy CS Tools

    Second day of VASS APCS training. Lots of fun stuff: