The goal of this activity is to introduce students to the variation that exists in a population of organisms. Students plant different seeds in a field with a gradient of sunlight. Their seeds survive the winter and grow into plants the following spring to reinforce the point that the evolutionary changes the students observe take place over many generations. In a second model, a plant produces seeds, some of which grow into plants that are slightly different from those of the parent plant. (Evolution Activity 2 of 10.)

The goal of this activity is to give students the opportunity to 'think like a scientist,' making hypotheses, doing experiments, making observations, and analyzing data. Students are encouraged to construct and conduct their own experiments with ecosystems comprising grass, rabbits, and up to two predator species: hawks and foxes. (Evolution Activity 10 of 10.)

The concept of interdependence in an ecosystem and its effect on the evolution of populations is further explored through a model of a dam. Students build a dam in the middle of the field, dividing the ecosystem in half to illustrate the effects of geographic isolation. They watch as the grass and then the rabbit populations in that region shift to one variant in the population. When students remove the dam, they observe the ecosystem slowly return to its original state. (Evolution Activity 8 of 10.)

In this activity, students review inheritance with variation. A Virtual Field model has light levels that vary smoothly from top to bottom. A single type of seed grows best in the center of the field, but the model includes variation in the offspring seeds. Since each plant scatters seeds randomly, it happens occasionally that some of these different seeds fall in a location where the light level is just right for it. When this happens the seed will grow into a healthy plant that will produce seeds of its own. In this way, the single type of plant eventually evolves into a full spectrum of different varieties. (Evolution Activity 3 of 10.)

This activity uses a model of the Virtual Ecosystem with three species in it: grass, rabbits, and hawks, enabling the students to explore the effect of predation on the prey population. At first students explore protective coloration as they 'become' a hawk and try to catch and eat brown and white rabbits on a snowy field. The latter blend into the background and are harder to see, so they have a selective advantage. Students then explore how the color of the rabbit population changes as the environment changes over time. (Evolution Activity 9 of 10.)

This transfer activity tests student understanding of variation and inheritance. It starts with five flower boxes, as in 'The Virtual Greenhouse,' and three types of seeds with variations in their roots. The flower boxes differ in the amount of water they receive, and students discover which seeds thrive in which environment. Students are then challenged to produce a crop of plants that can grow everywhere in a field by taking advantage of the small variation in root type from one generation to the next. (Evolution Activity 5 of 10.)

The goal of this activity is to introduce students to how variation in organisms can enable them to live in different environments. For example, plants with different sizes of leaves are adapted to grow under different amounts of light. Students plant three different types of seeds in five different flower boxes and are challenged to determine the light level under which each type of seed grows best. (Evolution Activity 1 of 10.)

Students discover that variation in plants allows some varieties to survive in near-drought conditions. Next, students learn that different types of rabbits prefer to eat different varieties of plants. Students make the connection between rainfall amount and the rabbit population's ability to survive by thinking first about rainfall and plants, then about plants and rabbits. Students discover that when certain plants cannot grow and reproduce, the rabbits that eat those plants will not have enough food to survive. (Evolution Activity 7 of 10.)

When J.J. Thomson first discovered that a cathode ray was actually a particle beam consisting of a stream of electrons, he concluded that these new particles were not just another type of atom. Explore and compare the behavior of electrons vs. charged atoms when they are shot through an electric field of varying intensity.

Explore the structure of various proteins and see how the nonpolar amino acids form the core of many protein structures.

Watershed Awareness using Technology and Environmental Research for Sustainability (WATERS)

The WATERS project is developing and researching a student-centered, place-based, and accessible curriculum for teaching watershed concepts and water career awareness for students in the middle grades. This 10-lesson unit includes online, classroom, and field activities. Students use a professional-grade online GIS modeling resource, simulations, sensors, and other interactive resources to collect environmental data and analyze their local watershed issues. The WATERS project is paving a path to increased access to research-based, open access curricula that hold the potential to significantly increase awareness of and engagement with watershed concepts and career pathways in learners nationwide.

This material is licensed under a Creative Commons Attribution 4.0 License. The software is licensed under Simplified BSD, MIT or Apache 2.0 licenses. Please provide attribution to the Concord Consortium and the URL https://concord.org.

Each page of this activity has a CODAP doc for recording data from sensors. This can be used for ad hoc experimentation or just messing around with sensors to learn how to use them. If not using sensors, the sensor interactive can be minimized and moved out of the way.

Explore a protein and its components using a simplified representation to see structure; or a view of all atoms to see full details.

Learn about exponential decay in real-world situations. Problems involve the application of depreciation of an asset and radioactive decay. Learn to apply exponential decay equations and interpret graphs. This is the last of three activities for teaching and learning about exponential functions in algebra: Graphing Exponential Equations; Exponential Growth; and Exponential Decay.

Learn about exponential growth in real-world situations. Problems involve the application of compound interest and exponential population growth. This is the second of three activities for teaching and learning about exponential functions in algebra: Graphing Exponential Equations, Exponential Growth and Exponential Decay.

Explore the role of size and shape in the strength of London dispersion attractions. While all molecules are attracted to each other, some attractions are stronger than others. Non-polar molecules are attracted through a London dispersion attraction; the strength of the attraction depends on the shapes and sizes of the interacting molecules. The force of attractions between molecules has consequences for their interactions in physical, chemical and biological applications.

Explore the potential and kinetic energy as two atoms form a covalent bond.

Explore the balance of forces and electron distribution as two atoms are moved closer and further apart.

To combat the common misconception that all mutations have large effects on proteins, students experiment with the Protein Synthesis Simulation to learn about the relationship among DNA, codons, amino acids, and proteins. At first, students investigate a strand of DNA that includes all 20 amino acids. Then, they make guided changes to discover that sometimes a single change can stop most of the protein from being formed, while another change produces no noticeable affect at all. Next, they complete challenges to mutate a DNA strand, and conclude with a mini-research project on mutations.

In this activity, students study gas laws at a molecular level. They vary the volume of a container at constant temperature to see how pressure changes (Boyle's Law), change the temperature of a container at constant pressure to see how the volume changes with temperature (Charles’s Law), and experiment with heating a gas in a closed container to discover how pressure changes with temperature (Gay Lussac's Law). They also discover the relationship between the number of gas molecules and gas volume (Avogadro's Law). Finally, students use their knowledge of gas laws to model a heated soda can collapsing as it is plunged into ice water.