**Transformations **(Geometry)

An informal introduction to translations, line reflections, and rotations as functions that map the plane onto the plane, highlighting key identifying properties of each

**Minimization Problem ** (Algebra and Functions)

A max/min problem appropriate for algebra I through calculus with opportunities to simplify expressions with CAS; to use literal algebraic symbols, tables of values, graphs, and other multiple representations.

**Seeing Parabolas** (Geometry)

An exploration of conic sections that engages students with three views of parabola: particular intersections of plane and cone, graphs of quadratic functions, and focus–directrix definition. The lesson includes the development of the equation of a parabola based on the focus–directrix definition. Example can be found through link connected to problem name.

**Relating Leg Length to Stride Length** (Data Analysis and Statistics)

A problem about examining a set of bivariate, quantitative data for patterns and relationships, affording opportunities to choose which tools to use, determine which items are giving valuable information, decide which model fits the data best—and defend those decisions.

**Donating Blood** (Simulation)

An investigation of the scenario in which random donors arrive at a blood center and we wish to determine the probability of a particular number having type B blood. (Teachers' Notes)

**Waiting for Blood Donors** (Simulation)

An investigation of the scenario in which the percent of donors having type B blood is known but we want to estimate the number of donors that will have to arrive in order to have a particular number of type B blood donors. (Teachers' Notes)

**Introduction to Geometric Transformations** (Geometry)

Informal introduction to explore properties of the congruence transformations, including translations, reflections, and rotations.