We introduce variations on the Fibonacci sequence such as the sequences where each term is the sum of the previous three terms, the difference of the previous two, or the product of the previous two. We consider the issue of the ratio of the successive terms in ways that reinforce key behavioral concepts of polynomials.

# Browse

### Eric Milou and Steve Leinwand

The standard high school math curriculum is *not* meeting the needs of the majority of high school students and that serious consideration of rigorous alternatives is a solution whose time has come.

### Charles F. Marion

The simplest of prekindergarten equations, 1 + 2 = 3, is the basis for an investigation involving much of high school mathematics, including triangular numbers, arithmetic sequences, and algebraic proofs.

### Victor Mateas

How trigonometry is used and portrayed differently in mathematics and physics textbooks highlights potential sources for student struggle, constraints on our trigonometry curriculum, and lessons learned when looking across STEM disciplines.

### Sara Gartland, Shellee Wong, and Laurie Silverstein

Co-teachers in a ninth-grade algebra 1 class offered instruction that integrates mathematical learning with social and emotional learning during hybrid (online and face-to-face) class meetings, promoting healing and positive identity development among students.

### Sarah Quebec Fuentes

Learn about strategies and tools to examine and improve your practice with respect to fostering equitable small-group, student-to-student discourse.

### Lauren R. Holden, Yi-Yin (Winnie) Ko, Devon W. Maxwell, Connor A. Goodwin, Cheng-Hsien Lee, Jennifer E. Runge, and Elizabeth B. Beeman

One-Straight-Cut-Heart activities can help teachers support students’ engagement with geometry and can deepen students’ geometric reasoning.

### Alisan Boes, Duane C. Boes, and Nichola Hillis

We explore the statistical likelihood of one, or more, siblings in a family of nine surviving to 100 years of age.

### Joshua David Jones

To be literate in a society where the information shared online is often exploited, learners should be exposed to multiple aspects of contemporary predictive modeling. Explore a lesson in which students learned an algorithm used in practice to automate the process of making recommendations.

### Hanan Alyami

During a Desmos activity, students adjust the measures of angles in radians to reposition a laser and a mirror so the beam passes through three stationary targets. The Radian Lasers activity can be extended to simulate project-based learning.