Source: Cyberchase: “Snelfu Snafu, Part 1”
Funding for the VITAL/Ready to Teach collection was secured through the United States Department of Education under the Ready to Teach Program.
In this video segment from Cyberchase, there is a valuable Encryptor chip being auctioned off that the CyberSquad needs to purchase in order to save Motherboard. It looks like it will take at least 100 Snelfus to win the bidding. The CyberSquad plans to raise Snelfus by working each day to earn and save Snelfus over a period of 11 days.
Investigations/Scott Foresman (2006)
Changes Over Time
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Here are some Frame, Focus and Follow-up suggestions for using this video in a math lesson.
What is Frame, Focus and Follow-up?
Frame: If you had to earn $50 to pay for an overnight class trip, and you only had 10 days to earn it, how much would you need to earn each day? Would it be better to try to earn it all in one day, or to spread the work out over a number of days? Why?
Focus: Watch to learn how the CyberSquad plans to earn the Snelfus they need to win the auction for the chip. How do they figure out how much they must earn each day in order to reach their goal? What kinds of math operations do they use?
Follow Up: Saving for the Encryptor chip takes the CyberSquad 11 days. When you are saving up for something, how can you keep track of your savings? How do you know how much you still need to earn? What do you do when you have to spend some of your savings? How do you keep track of that?
JACKIE: Hmmm, I guess when you save a little at a time and you keep on doing it over and over, it adds up. What just a minute. What if we did that with Snelfus?
DIGIT: Do what?
JACKIE: Save snelfus. The auction doesn’t end for eleven days. That gives us time.
MATT: Only one problem. Where do we get the snelfus to save?
JACKIE: We earn them. We get jobs. If we earn and save even a little bit everyday for eleven days. The total will add up. And we can bid on the chip
AUCTIONEER: You’re the cheapest bunch of borgs I ever saw. This chip is priceless. Thirty-five snelfus is nothing.
BIDDER: I bid fifty snelfus.
AUCTIONEER: Fifty snelfus. Now we’re bidding.
SLIDER: I think the way this auction is going we’re going to need at least a hundred snelfus to get that chip.
JACKIE: Oh man, how can we save a hundred snelfus in just eleven days?
DIGIT: Let’s see, if we saved one a day like I did with these caps, it would take, yikes, a hundred days to save a hundred snelfus.
MATT: Time out. We don’t have a hundred days. We only have eleven.
INEZ: So what would happen if we saved ten snelfus a day instead of one? That work?
JACKIE: Lets try. Say this cap is ten snelfus. On the first day we would save ten snelfus. On day two we save another ten, which makes our total savings twenty snelfus.
MATT: So the total goes up by ten each day. Hey a pattern!
INEZ: Twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety and on the tenth day our total reaches one hundred. Cool.
JACKIE: This plan’s going to work. If we save ten snelfus a day. We know for sure we’ll have our hundred snelfus in exactly ten days.
DIGIT: OK, Gang, let’s count up what we earned. Two, four, six, eight, ten. Day one. Ten snelfus saved.
MATT: Cool, just the amount we planned.
JACKIE: And if we keep saving ten snelfus a day for nine more days, we’ll have enough to buy the chip and save Motherboard.
INEZ: Every day, the total’s going to grow and grow.
DIGIT: I’m going to have to grow more wings to hold it all.
SLIDER: No problem. I’ll rig up a bank. We stash our cash in here. It will show how much we save each day. Our goal: the big one hundred.
JACKIE: Let’s make a deposit.
MATT: I have to admit, Slider, that’s pretty cool.
JACKIE: Pretty cool? I think it’s awesome.
INEZ: Me too. I can’t wait to do it again tomorrow.