The Geoboard is a tool for exploring a variety of mathematical topics introduced in the elementary and middle grades. Learners stretch bands around pegs to form line segments and polygons and make discoveries about perimeter, area, angles, congruence, fractions, and more.
This virtual version of the manipulative is an open-ended educational tool, ideal for elementary classrooms and other learning environments that use iPod Touches, iPhones, or iPads.

During this lesson, students start to see the data structure they will use to store their images, towards finding a solution to this unit's Grand Challenge. Students are introduced to two-dimensional arrays and vector classes. Then they are guided to see that a vector class is the most efficient way of storing the data for their images. Grand Challenge: To write a program to simulate peripheral vision by merging two images.

Students examine how the orientation of a photovoltaic (PV) panel relative to the sun affects the efficiency of the panel. Using sunshine (or a lamp) and a small PV panel connected to a digital multimeter, students vary the angle of the solar panel, record the resulting current output on a worksheet, and plot their experimental results.