The goal of this task is to have students appreciate how the different constants (P0, K, and r) influence the shape of the graph.

This problem introduces a logistic growth model in the concrete setting of estimating the population of the U.S. The model gives a surprisingly accurate estimate and this should be contrasted with linear and exponential models, studied in ``U.S. Population 1790-1860.'' This task requires students to interpret data presented.

Students analyze data on temperature and precipitation collected from 26 different Long Term Ecological Research sites and compare them with annual net primary productivity. The students then form an ecological rule to explain their results.

In this activity students compare objects to see which is longer and heavier than the other.

In this task students figure out how to draw the longest line on a map of the United States without hitting a border. They use color and line plots to keep track of their results.

This activity involves student teams classifying clouds into the main categories, making a poster of their findings, having a poster session and learning the vocabulary terms cirrus, stratus and cumulus.

Loopy dot diagrams uses fruit loops as a manipulative to help students develop the basic skills for making Lewis dot structures to model covalent bonding.

This task builds on studentsŐ prior knowledge and understanding of conditional probability, and introduces the concept of independence of events.

Students work in teams of two to discover the relative positions of the Earth, Sun and Moon that produce the different phases of the Moon. Groups are each given a Styrofoam ball that they attach to a pencil so that it looks like a lollipop. In this acting-out model exercise, this ball on a stick represents the Moon, the students represent the Earth and a hanging lightbulb serves as the Sun. Students move the "Moon" around them to discover the different phases. They fill in the position of the Moon and its corresponding phase in a worksheet.

Students learn about the unique challenges astronauts face while eating in outer space. They explore different food choices and food packaging. Students learn about the engineering design process, and then, as NASA engineering teams, they design and build original model devices to help astronauts eat in a microgravity environment --- their own creative devices for food storage and meal preparation.

The purpose of this task is for students to compare two options for a prize where the value of one is given $2 at a time, giving them an opportunity to "work with equal groups of objects to gain foundations for multiplication." This context also provides students with an introduction to the concept of delayed gratification, or resisting an immediate reward and waiting for a later reward, while working with money.

In this activity, students gain first-hand experience with the mechanical advantage of pulleys. Students are given the challenge of helping save a whale by moving it from an aquarium back to its natural habitat into the ocean. They set up different pulley systems, compare the theoretical and actual mechanical advantage of each and discuss their recommendations as a class.

In this activity, learners explore the "nuts and bolts" of gene chips. Learners construct a simple model of a DNA microarray (also known as gene chips) and learn how microarrays can be used to identify and treat disease--including cancer. This resource includes references and an explanation of microarrays.

A short activity using goldenrod copy paper as an indicator to introduce neutralization reactions. Students describe what they beleive happens during this reaction.

In this activity, students reinforce their understanding of compound machines by building a catapult. This compound machine consists of a lever and a wheel-and-axel. Catapults have been designed by engineers for a variety of purposes from lifting boulders into the air for warfare to human beings for entertainment; the projectiles in this activity are grapes for a magic act. Given the building materials, students design and build their catapult to launch a grape a certain distance.

A magical demonstration where a Pyrex tube vanishes in a beaker of mineral oil. Useful demonstration to introduce to concept of refraction (and/or partial reflection).

This lesson introduces students to the effects of magnetic fields in matter addressing permanent magnets, diamagnetism, paramagnetism, ferromagnetism, and magnetization. First students must compare the magnetic field of a solenoid to the magnetic field of a permanent magnet. Students then learn the response of diamagnetic, paramagnetic, and ferromagnetic material to a magnetic field. Now aware of the mechanism causing a solid to respond to a field, students learn how to measure the response by looking at the net magnetic moment per unit volume of the material.

Students explore electromagnetism and engineering concepts using optimization techniques to design an efficient magnetic launcher. Groups start by algebraically solving the equations of motion for the velocity at the time when a projectile leaves a launcher. Then they test three different launchers, in which the number of coils used is different, measuring the range and comparing the three designs. Based on these observations, students record similarities and differences and hypothesize on the underling physics. They are introduced to Faraday's law and Lenz's law to explain the physics behind the launcher. Students brainstorm how these principals might be applied to real-world engineering problems.

This lesson ties the preceding lessons together and brings students back to the grand challenge question on MRI safety. During this lesson, students focus on the logistics of magnetic resonance imaging as well as the MRI hardware. Students can then integrate this knowledge with their acquired knowledge on magnetic fields to solve the challenge question.