Explore how populations change over time in a NetLogo model of sheep and grass. Experiment with the initial number of sheep, the sheep birthrate, the amount of energy sheep gain from the grass, and the rate at which the grass re-grows. Remove sheep that have a particular trait (better teeth) from the population, then watch what happens to the sheep teeth trait in the population as a whole. Consider conflicting selection pressures to make predictions about other instances of natural selection.

This task is designed to give students insight into the effects of translations, rotations, and reflections on geometric figures in the context of showing that two figures are congruent.

Students' first experience with transformations is likely to be with specific shapes like triangles, quadrilaterals, circles, and figures with symmetry. Exhibiting a sequence of transformations that shows that two generic line segments of the same length are congruent is a good way for students to begin thinking about transformations in greater generality.

This task has two goals: first to develop student understanding of rigid motions in the context of demonstrating congruence. Secondly, student knowledge of reflections is refined by considering the notion of orientation in part (b).

This webinar (recorded Sept. 27, 2017) introduces how to connect other services as add-ons to projects on the Open Science Framework (OSF; https://osf.io). Connecting services to your OSF projects via add-ons enables you to pull together the different parts of your research efforts without having to switch away from tools and workflows you wish to continue using. The OSF is a free, open source web application built to help researchers manage their workflows. The OSF is part collaboration tool, part version control software, and part data archive. The OSF connects to popular tools researchers already use, like Dropbox, Box, Github and Mendeley, to streamline workflows and increase efficiency.

The purpose of this task is to have students think about the meaning of multiplying a number by a fraction, and to use this understanding of fraction multiplication to make sense of the commutative property of multiplication in the case of fractions.

This article from the free online magazine Beyond Weather and the Water Cycle provides appropriate science lessons for Grades K-5. The focus is on acquainting young learners with climate-change concepts that are not too complex for their grade level and will not frighten them. In each issue, the magazine develops articles around one of the seven essential principles of climate science. The author believes early lessons about water availability and extreme weather events will prepare students for complex climate concepts they will encounter in later grades.

This video will go over three issues that can arise when scientific studies have low statistical power. All materials shown in the video, as well as the content from our other videos, can be found here: https://osf.io/7gqsi/

Students analyze video clips of kids rolling down a hill on skates, scooters, and bikes to determine whether mechanical energy is conserved.

A high speed video clip of a roller coaster is used as an example of conservation of mechanical energy. Students use the video to determine whether mechanical energy is conserved while the roller coaster rolls up, and then back down a hil.

This active demonstration investigates the law of conservation of momentum using a person on rollerblades and a thrown medicine ball.

Students are introduced to the idea of improving efficiency by examining a setting that is familiar to many teenagers fast food restaurants. More specifically, they learn about the concepts of trade-offs, constraints, increasing efficiency and systems thinking. They consider how to improve efficiency in a struggling restaurant through delegating tasks, restructuring employee responsibilities and revising a floor plan, all while working within limitations and requirements. Finally, students summarize and defend their suggested changes in argumentative essays.

An interactive lecture in which students use data on feeding habits and habitat, skeletons, and DNA sequences to draw phylogenetic trees.

The construction of the perpendicular bisector of a line segment is one of the most common in plane geometry and it is undertaken here. In addition to giving students a chance to work with straightedge and compass, the problem uses triangle congruence both to show that the constructed line is perpendicular to AB and to show that it bisects AB.

Successful completion of this cooperative learning activity requires the active involvement of the individual, the small group and the entire classroom (collaboration). The goal is to make a simple task as complicated as possible by constructing a single complex machine.

This online quiz on sustainable development can be used in French language classes to prepare intermediate-level students for discussions on environmental topics. The resource is excellent for immersion and content-based instruction.

Context Rich Problem on demand shifters and the implications of such a shift.

In this activity, students use a variety of materials to design and create headphones that absorb sound.

This activity describes the construction and use of a pneumatic cannon and free falling target used to teach the concepts of projectile motion in introductory physics.

This task is for instruction purposes. Part (b) is subtle and the solution presented here uses a "dynamic" view of triangles with two side lengths fixed. This helps pave the way toward what students will see later in trigonometry but some guidance will likely be needed in order to get students started on this path.