Teachers' Domain is moving soon to its new and improved home — PBS LearningMedia!          Learn More

# Speed of Ascent

Media Type:
Video

Running Time: 2m 03s
Size: 5.6 MB

or

Source: Cyberchase: “Double Trouble”

### Collection Developed by:

Collection Credits

### Collection Funded by:

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, Hacker and the CyberSquad race each other to try to reach the Good Vibration, which is set on top of a tall monument. Two sets of stairs have appeared and Hacker chooses the one with larger steps in order to reach the top faster. The CyberSquad must use the stairs with smaller steps, but they soon notice that the number of steps in their staircase increase at a different rate than in Hacker's staircase.

Connections

Everyday Math (2004)
Teacher Lesson Guide: pp. 105, 462, 920
Teacher Reference Manual: pp. 145-148.
Student Reference Book: pp. 69

Teaching Tips

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: Sometimes when we see a consistent pattern occurring we can record it using numbers and symbols. In math this is commonly called an expression. Think about patterns you may have observed, particularly those where something increases or decreases. Can you describe a pattern like this and record it in some way?

Focus: In this segment, watch as the two sets of stairs appear. See if you can identify the pattern in the number of steps in each staircase. [Note: Pause the segment after any increase, and ask students to predict which set of steps will reach the top first.]

Follow Up: Can you describe how each of the two staircases increased? Was there a pattern in each? Could you record that pattern as a mathematical expression? How else might the steps have increased, and what would that pattern look like written down as an expression?

Transcript

JACKIE: Here we go again!

DIGIT: Wait a minute! These steps go higher than the last ones!

JACKIE: You’re right! We went up four steps this time not two!

MATT: C’mon, Inez, up you go!

INEZ: Guys! Remember how the lily pads doubled and grew so fast?

JACKIE: Yeah.

INEZ: Well, I think our steps are doubling, too!

INEZ: See? Hacker’s big steps are increasing at A steady rate, one more each time. One, two, three, four…

INEZ: But look at our steps! One-two-four-eight… Even though our steps are smaller, they’re doubling each time!

JACKIE: So our next step should be eight doubled ...or sixteen! We pick up eight steps!

MATT: And since Hacker’s keep going up at a steady rate, he’ll only pick up one.

JACKIE: Man, doubling is so much faster!

INEZ: Oh, no! If we do get sixteen it’ll be too high to climb!

MATT: No problem!

DIGIT: Here come the steps.

KIDS: NOW!!!

JACKIE: Sixteen! It did double!

DIGIT: We’re gonna catch you, Hacker!

HACKER: You couldn’t catch a cold!

JACKIE: How many stairs do we get next?

INEZ : Well, sixteen doubled is...

DIGIT: Thirty two!

MATT: That could take us all the way to the top!

KIDS/DIGIT: NOWWWW!!!

HACKER: What?!

MATT: Whatever happens, we can’t let Hacker get the Good Vibration and ruin Shangri La!

Standards

to: