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TTLC 2026 · Teaching & Learning Conference

Building Trust Through
Transparency

Teaching mathematics in the browser — no black boxes, no installs, no barriers

Instructional Assistant Professor · Department of Mathematics
Texas A&M University · College Station, TX
QR code linking to https://shelvean.github.io/math-tools/ttlc2026.html Slides online

Why this talk? 🤔

TTLC 2026 Mathematics · Texas A&M

Students today use more computational tools than any generation before them — and understand fewer of them.

  • 🧮  They reach for CAS, graphing calculators, homework-system widgets, and now LLMs
  • 📦  Each tool is a black box — an answer comes out, and the machinery stays hidden
  • 📉  Trust in the tool becomes a substitute for understanding the mathematics
  • 🎯  I want to argue: transparency is what turns a computational tool into a learning tool

The imagination barrier 🧠

TTLC 2026 Mathematics · Texas A&M

Textbooks routinely ask students to do a very hard thing: run a mental movie of a physical system.

  • 📖  "Now imagine the pendulum at small amplitude, with light damping, being driven at resonance…"
  • 🎞️  Mental simulation is the skill students are trying to develop — not a skill they already have
  • ⚠️  Symbolic notation alone is a thin channel; equations and intuition drift apart when the dynamics stay invisible
  • 💡  If we want understanding, we have to give the dynamics somewhere to show up

Black boxes are everywhere 📦

TTLC 2026 Mathematics · Texas A&M

The default tools students encounter in math courses today hide their mechanism by design.

  • 🔒  CAS and symbolic engines: you type an integral, you get an answer — no steps, no derivation
  • 📱  Graphing calculators and online homework systems: closed code, proprietary formats, black-box grading
  • 💬  LLM chatbots: confident prose, no reproducibility, no way to inspect why a particular step appeared
  • 🧪  The student cannot audit the reasoning, and neither can the instructor — trust is taken on faith

Transparency as a pedagogical commitment ✨

TTLC 2026 Mathematics · Texas A&M
A transparent tool is one the student — and the instructor — can take apart and put back together.
  • 👀  View source: every formula, every numerical method, every visual choice is readable JavaScript
  • 🔁  Reproducible: same input produces the same output, on any device, with no hidden seed or remote call
  • 🏠  Local: runs entirely in the browser — no login, no account, no proprietary server
  • 🛠️  Forkable: a colleague can copy the tool, modify it for their own course, and host their own version
  • 🎓  This is what invites trust — not a promise, but an audit trail

The portfolio, at a glance 🌍

TTLC 2026 Mathematics · Texas A&M

Sixteen months of building, freely shared on GitHub Pages. Analytics snapshot, April 2026:

60+
interactive tools
123K
page views
7,729
active users
118
countries
scan: about QR code linking to https://shelvean.github.io/math-tools/about.html

Math 308: Differential Equations 📐

TTLC 2026 Mathematics · Texas A&M

Engineering students learn best when the math has a physical referent — and when they can poke that referent.

🏗️ Physical system
pendulum, spring,
circuit, chemical reactor
📈 ODE model
mẍ + cẋ + kx = F(t)
🖱️ Interactive tool
slider → dynamics
visible in the browser
  • ⚙️  Mass-spring-damper, coupled multi-mass systems, forced oscillations with resonance sweep
  • 📈  Phase portraits: drop initial conditions, watch saddles, spirals, and centers emerge live
  • 🌀  Van der Pol, Duffing, logistic map, cobweb & bifurcation diagrams
  • 🔣  Step-by-step tutorial tools: integrating factor, Wronskian, exact equations, undetermined coefficients

Oscillations: from one mass to many 〰️

TTLC 2026 Mathematics · Texas A&M

The same equation of motion scales from a single damped oscillator to a chain of coupled masses with three normal modes — every step is something the student can drive with a slider.

Four-mass-spring chain showing equilibria and current displacements
Vertical hanging mass on a spring

Single damped mass on a vertical spring — the canonical mẍ + cẋ + kx = 0. Slide damping → exponential envelope visibly contracts. Resonance sweep makes the peak appear instead of being derived.

  • 🎚️  One mass: drag damping, drag stiffness, watch the envelope reshape in real time
  • 🔁  Add a forcing term and sweep ω — the resonance peak emerges, not derived
  • 🔗  Couple two masses → beating; four masses → three normal modes you can pick out by eye
  • 📐  Each mass's displacement xᵢ(t) prints live underneath the picture
  • 🧮  Integrator and force calculation are readable JavaScript — no opaque physics engine
scan to try QR code linking to https://shelvean.github.io/math-tools/massspring-horizontal.html

Phase portraits: exploration over draftsmanship 📈

TTLC 2026 Mathematics · Texas A&M

Hand-drawing phase portraits used to be the lesson. With a live tool, it becomes a five-minute warmup — and the time goes to interpretation.

Phase portrait showing a saddle: hyperbolic trajectories with two diagonal eigenvector lines
Saddle · real eigenvalues, opposite sign
Phase portrait showing a spiral sink: trajectories spiraling toward the origin
Spiral sink · complex eigenvalues, neg. real part
  • 🖱️  Click anywhere — a trajectory unrolls from that initial condition in real time
  • ↗️  Eigenvector lines update live as students change the matrix entries
  • 🎚️  Sweep one parameter and watch a saddle morph into a spiral as eigenvalues turn complex
  • ✍️  The hand-drawing exercise becomes a warmup, not the lesson
  • 🧭  Time freed up for the real question: what does each picture say about stability?
scan to try QR code linking to https://shelvean.github.io/math-tools/linearportrait.html

Linear programming, by clicking on corners 📐

TTLC 2026 Mathematics · Texas A&M

The Method of Corners stops being a checklist of algebra and starts being something the student can see: a feasible region, its vertices, and the objective sliding across them.

Method of Corners: feasible region with corner points and objective value at the optimum
  • 🧱  Type any constraints — the half-planes are shaded and intersected into a feasible region in real time
  • 📍  Corner points are computed automatically and the objective is evaluated at each one
  • 🎯  The maximum (or minimum) is highlighted, including the degenerate case where the optimum lies along an entire edge
  • 🧮  Business-math and finite-math students get a geometric foothold before they ever meet the simplex algorithm
scan to try QR code linking to https://shelvean.github.io/math-tools/corners.html

Dynamical systems: the subject begs for pictures 🌀

TTLC 2026 Mathematics · Texas A&M

If any topic in the curriculum is intrinsically visual, it is dynamical systems — and yet on paper it lives as algebra. The browser is where the algebra and the picture finally meet.

Duffing oscillator: physical view (mass in a double-well potential), phase portrait in (x, ẋ), and displacement x(t) vs time
  • 🪨  Physical view: a mass moving in a double-well potential — the geometry students should picture before any equation
  • 🎯  Phase portrait (x, ẋ): the strange attractor emerges as the trajectory threads between the two wells
  • 📈  Displacement vs time: chaotic time series, color-coded by speed, links the picture to the data students would actually measure
  • 🎚️  Drag a slider — damping, forcing, frequency — and watch limit cycles, period doubling, and chaos appear
scan to try QR code linking to https://shelvean.github.io/math-tools/dynamical.html

Why JavaScript? A runtime question 💻

TTLC 2026 Mathematics · Texas A&M

The language choice matters because the question isn't "what is fastest to build?" — it's "what will still run in ten years, on any device, without friction?"

RuntimeReachFriction for the student
Java applets obsolete browser support removed
Maple / MATLAB licensed, installed institutional account, local install
Python universal in principle Python install, pip, venv, matplotlib
JavaScriptevery browser, every deviceopen the link — that's it

For core mathematics the tools have zero runtime dependencies — the math is JavaScript, not a library call.

The workflow has changed — 2025 → 2026 🤖

TTLC 2026 Mathematics · Texas A&M

A subtle but enormous shift in what a single instructor can maintain. The tools did not change. The way they get edited did.

⌨️  2025 — hand-prompting

  • Chatbot in one window, text editor in another
  • Copy JavaScript, paste, debug, test, commit — one HTML file at a time
  • Cross-cutting changes (new navigation, a11y labels) meant editing dozens of files by hand
  • Consistency across the portfolio drifted — easily

✨  2026 — agentic editing (Claude Code)

  • One prompt edits many files — e.g., "add ARIA labels to every visualization"
  • The agent tests, iterates, and commits directly to GitHub
  • Portfolio-wide refactors happen in a single afternoon instead of a week
  • Consistency becomes a feature, not a burden

Accessibility is the test ♿

TTLC 2026 Mathematics · Texas A&M

A tool isn't transparent if it's only transparent to sighted users with a mouse. WCAG 2.1 AA is the honest benchmark.

  • 👁️  Visual: high-contrast palette, scalable typography, visible keyboard focus rings throughout
  • ⌨️  Keyboard: every slider, every button, every control reachable without a pointing device
  • 🔊  Assistive: MathJax + MathCAT pipeline so equations are read aloud correctly by screen readers
  • 🏷️  Semantic: ARIA labels, table captions, landmark regions — propagated across the portfolio with agentic edits
  • 📚  This aligns with Provost OER priorities — the Math 308 question bank I'm building now is being designed accessibility-first

Where this is going 🧭

TTLC 2026 Mathematics · Texas A&M

"Your work is just wonderful."

— Gilbert Strang, MIT (summer 2025)

"They are beautiful! Very elegant."

— Steven Strogatz, Cornell (summer 2025)

Open any of the 60+ tools at:

shelvean.github.io/math-tools

No account, no install, no cost — forever-free OER. Fork it, remix it, use it in your own course.

← / → to navigate · click QR to open tool