**OPTIMAL: On-line Preparation Tools for Instructional Materials and Assessment of Learning**

These demonstrations show some of the capabilities of OPTIMAL. The purpose of OPTIMAL is to allow instructors to develop interactive, on-line course materials, compare different methods of instruction in their courses using these materials, and deploy these different methods to their students using proper experimental control, counter-balancing, and randomization. The crucial architectural underbelly of OPTIMAL is the jsPsych library for conducting on-line experiments in Javascript, developed by Joshua de Leeuw. The open source software repository for jsPsych is available here and here is the Behavioral Research Method paper describing it.

**Demonstrations**

- Different mathematical concepts of central tendency: mode, median, and mean. Learners decide whether to give themselves examples of the same or different concept with the same or different example (with Paulo Carvalho, David Braithwaite, Joshua de Leeuw, and Robert Goldstone)
- The game of Nim, which teaches Combinatorial Game Theory, as well binary number representations and their application to game theory (with Robert Goldstone and Eleanor Goldstone)
- The mathematics of combinatorics (with David Braithwaite and Robert Goldstone). See Papers 1 and 2 and 3
- Free sorting birds into categories by moving them into spatial groups (with Josh de Leeuw, Paulo Carvalho, and Robert Goldstone; materials courtesy of Jacoby, Wahlheim, & Coane, 2010)
- Learning about psychology concepts related to decision by categorizing examples (with Paulo Carvalho and Robert Goldstone, based on materials developed by Rawson, Thomas, & Jacoby, 2015)
- Learning categories by discovering new features and rules (with Erik Weitnauer, Paulo Carvalho, and Robert Goldstone). See Papers 1 and 2
- Binomial and Power Law distributions (with David Braithwaite and Robert Goldstone). See Paper 1
- Categorizing situations into those involving sampling with versus without replacement (with David Braithwaite and Robert Goldstone). See Papers 1 and 2
- A graphic and interactive method for teaching about binomial distributions and the parameters that govern their shape (with David Braithwaite and Robert Goldstone)
- Main effects and interactions in research design, using graphs and/or tables to represent data (with David Braithewaite and Robert Goldstone). See Papers 1 and 2
- An Interactive, graphic approach to sampling without replacement (with Jason Sprinkle, David Braithwaite, and Robert Goldstone)