The purpose of this task is to help solidify students' understanding of signed numbers as points on a number line and to understand the geometric interpretation of adding and subtracting signed numbers.

This task has students experiment with the operations of addition and multiplication, as they relate to the notions of rationality and irrationality.

In this ordering task each number has at most 3 digits so that students have the opportunity to think about how digit placement affects the size of the number.

In this task students must place 4-digit numbers into order from smallest to greatest and greatest to smallest.

The purpose of this task is to extend students' understanding of fraction comparison.

In this task students compare numbers less than 100 to benchmark numbers and learn to build an understanding of the relative magnitude of numbers.

The purpose of this task is to present students with a situation in which they need to divide a whole number by a unit fraction in order to find a solution.

This challenging problem and brainteaser gives students an opportunity to compose and decompose polygons to make rectangles.

Student groups are challenged to create food packages for specific foods. They focus on three components in the design of their food packages; the packages must keep the food clean, protect or aid in the physical and chemical changes that can take place in the food, and present the food appealingly. They design their packaging to meet these requirements.

The purpose of this task is to provide students an opportunity to use mathematics addressed in different standards in the same problem.

The purpose of this task is for students to find the answer to a question in context that can be represented by fraction multiplication. This task is appropriate for either instruction or assessment depending on how it is used and where students are in their understanding of fraction multiplication.

The purpose of this task is to provide students with a situation in which it is natural for them to divide a unit fraction by a non-zero whole number.

Vision is the primary sense of many animals and much is known about how vision is processed in the mammalian nervous system. One distinct property of the primary visual cortex is a highly organized pattern of sensitivity to location and orientation of objects in the visual field. But how did we learn this? An important tool is the ability to design experiments to map out the structure and response of a system such as vision. In this activity, students learn about the visual system and then conduct a model experiment to map the visual field response of a Panoptes robot. (In Greek mythology, Argus Panoptes was the "all-seeing" watchman giant with 100 eyes.) A simple activity modification enables a true black box experiment, in which students do not directly observe how the visual system is configured, and must match the input to the output in order to reconstruct the unseen system inside the box.

This high level task is an example of applying geometric methods to solve design problems and satisfy physical constraints. This task is accessible to all students. In this task, a typographic grid system serves as the background for a standard paper clip.

Using paper, paper clips and tape, student teams design flying/falling devices to stay in the air as long as possible and land as close as possible to a given target. Student teams use the steps of the engineering design process to guide them through the initial conception, evaluation, testing and re-design stages. The activity culminates with a classroom competition and scoring to evaluate how each team's design performed.

This task assumes students have an understanding of the relationship between functions and equations. Using this knowledge, the students are prompted to try to solve equations in order to find the inverse of a function given in equation form: when no such solution is possible, this means that the function does not have an inverse.

The difference between an architect and an engineer is sometimes confusing because their roles in building design can be similar. Students experience a bit of both professions by following a set of requirements and meeting given constraints as they create a model parking garage. They experience the engineering design process first-hand as they design, build and test their models. They draw a blueprint for their design, select the construction materials and budget their expenditures. They also test their structures for strength and find their maximum loads.

The purpose of this task is to investigate the meaning of the definition of function in a real-world context where the question of whether there is more than one output for a given input arises naturally. In more advanced courses this task could be used to investigate the question of whether a function has an inverse.

The point of this task is to emphasize the grouping structure of the base-ten number system, and in particular the crucial fact that 10 tens make 1 hundred.

Students apply concepts of disease transmission to analyze infection data, either provided or created using Bluetooth-enabled Android devices. This data collection may include several cases, such as small static groups (representing historically rural areas), several roaming students (representing world-travelers), or one large, tightly knit group (representing urban populations). To explore the algorithms to a deeper degree, students may also design their own diseases using the App Inventor framework.