Students are introduced to the concept of engineering biological organisms and studying their growth to be able to identify periods of fast and slow growth. They learn that bacteria are found everywhere, including on the surfaces of our hands. Student groups study three different conditions under which bacteria are found and compare the growth of the individual bacteria from each source. In addition to monitoring the quantity of bacteria from differ conditions, they record the growth of bacteria over time, which is an excellent tool to study binary fission and the reproduction of unicellular organisms.

Try your hand at assembling the following bacteria jigsaw puzzle created with a Streptococcus image from CELLS alive! This puzzle is 32 pieces and generally takes a few minutes to solve.

Spreadsheets Across the Curriculum module. Students tabulate and graph data on bacteria density vs. time for a culture. Data start with innoculation and progress through the peak and decline.

Students explore static electricity by rubbing a simulated balloon on a sweater. As they view the charges in the sweater, balloon, and adjacent wall, they gain an understanding of charge transfer. This item is part of a larger collection of simulations developed by the Physics Education Technology project (PhET). The simulations are animated, interactive, and game-like environments.

In the open ocean around the Bahamas, pods of wild Spotted Dolphins frolic in the sunshine. Sometimes, they get bored and approach boats. In this educational video, Jonathan joins dolphin expert Wayne Scott Smith to learn how dolphins interact with each other. Jonathan learns how to play the Bandana Game, a game of -keep away- that the dolphins invented and like to play with Scott. Please see the accompanying study guide for educational objectives and discussion points.

In the master-equation formalism, a set of differential equations describe the time-evolution of the probability distribution of an ensemble of systems. This can be used, for example, to describe the varied mRNA copy numbers found in individual cells in a population.

The stochastic simulation algorithm (SSA, Kinetic Monte Carlo, Gillespie algorithm) produces an example trajectory for a particular member of a probabilistic ensemble by looping over the following steps. The current state of the system is used to determine the likelihood of each possible chemical reaction in relative comparison to the likelihoods for the other possible reactions, as well as to determine when the next reaction is expected. Pseudo-random numbers are drawn to "roll the dice" to determine exactly when the next reaction will proceed, and which kind of reaction it will happen to be.

This video segment from the Nevada Department of Wildlife looks at various species of bats and how they impact the environment.

This OLogy activity shows kids that there are simple, but very helpful things they can do to protect the ocean, even if they live nowhere near the water. It has a checklist of 14 ways kids can be ocean helpers that includes asking for tap water instead of bottled water and leaving plants and animals where they find them. For each of the checklist items, kids can check either "I am doing this" or "I could do this."

This Nature video segment focuses on the four foods most important to the grizzly bears' survival, and it describes the threats to the supply of each of them.

In this video segment from Nature, learn about the problems bears are creating on ranch land surrounding Yellowstone National Park.

This Nature video segment explores how the relationship between humans and grizzly bears has changed over the course of American History, and it describes the closing of the Yellowstone National Park garbage dumps in the 1970s.

Learn about the precautions humans must take in the face of a growing grizzly bear population in this video from Nature.

This video segment explores the world of the beaver, including the biology of the species and, more importantly, its ability to transform an ecosystem for its own benefit.

This video segment describes how the Australopithecus afarensis skeleton known as Lucy could have been fossilized. Footage courtesy of NOVA: "In Search of Human Origins."

This video segment from NOVA: "The Mystery of Animal Pathfinders" explores honeybee communication and navigation.

The PhET project at the University of Colorado creates "fun, interactive, research-based simulations of physical phenomena." This particular one deals with Beer's Law. "The thicker the glass, the darker the brew, the less the light that passes through." Make colorful concentrated and dilute solutions and explore how much light they absorb and transmit using a virtual spectrophotometer! The simulation is also paired with a teachers' guide and related resources from PhET. The simulation is also available in multiple languages.

This interactive shows the extent of the killing of lodgepole pine trees in western Canada. The spread of pine beetle throughout British Columbia has devastated the lodgepole pine forests there. This animation shows the spread of the beetle and the increasing numbers of trees affected from 1999-2008 and predicts the spread up until 2015.

This is an activity that involves students modeling the behavior and competition that Charles Darwin's finches would have gone through as they competed for food and space on the Galapagos Islands. Some will survive. Some won't.

Cocos Island, a remote volcanic summit in the middle of the Pacific Ocean, serves as a beacon for hungry predators, including thousands of hammerhead sharks that travel here each year in search of prey. This video segment from NOVA: "Island of Sharks" depicts some of the common predator-prey interactions that take place in the nutrient-rich waters surrounding the island.