## Search Results

### Analyze the Data

9-12
Sea gulls and crows feed on various types of mollusks by lifting them into the air and dropping them onto a rock to break open their shells. Biologists have observed that northwestern crows consistently drop a type of mollusk called a whelk from a mean height of about 5 meters. The crows appear to be selective; they pick up only large-sized whelks. They are also persistent. For instance, one crow was observed to drop a single whelk 20 times. Scientists have suggested that this behavior is an example of decision-making in optimal foraging.

### Looking Back and Moving Forward

9-12
As you review student work in this unit, it is important to remember the mathematical objectives/expectations of this Unit Plan that are stated in Principles and Standards for School Mathematics.

### Components of a Vector

9-12
In this lesson, students manipulate a velocity vector to control the movement of a car in a game setting. Students learn that vectors are composed of two components: magnitude and direction.

### Sums of Vectors and Their Properties

9-12
This example illustrates how using a dynamic geometrical representation can help students develop an understanding of vectors and their properties, as described in the Number and Operations Standard. Students manipulate a two vectors to control the movement of a plane in a game-like setting. Students extend their knowledge from the first lesson to further investigate the system of vectors.

### Pi Line

9-12
Students measure the diameter and circumference of various circular objects, plot the measurements on a graph, and relate the slope of the line to π, the ratio of circumference to diameter.

### Pedal Power

9-12
In this lesson, students investigate slope as a rate of change. Students compare, contrast, and make conjectures based on distance-time graphs for three bicyclists climbing to the top of a mountain.

### Caesar Cipher

9-12
In this lesson, students will investigate the Caesar substitution cipher. Text will be encoded and decoded using inverse operations.

### Exploring Measurement, Sequences, and Curves with Stringed Instruments

9-12
Students will measure lengths on stringed musical instruments, and discuss how the placement of frets on a fretted instrument is determined by a geometric sequence.

### Fretting

9-12
In the second lesson of this unit, students will use their discoveries from the first lesson to place frets on a fretless instrument. They will then compare geometric sequences with exponential functions.

### Light It Up

9-12

In this cooperative learning activity, students are presented with a real-world problem: Given a mirror and laser pointer, determine the position where one should stand so that a reflected light image will hit a designated target.

This investigation allows students to develop several rational functions that models three specific forms of a rational function. Students explore the relationship between the graph, the equation, and problem context.