Units are checked
Adding metres to seconds is refused before the model is ever called.
A real blackboard. Chalk and all.
A blackboard that reads the chalk.
Write x² sin x by hand. Aptus does not photograph the board and hand the picture to a machine to guess at. It receives the structured state of what is written: every fraction, every exponent, every unit, every edge of a solid. The mentor answers in brass, in the margin.
Nothing to install. No password.
A line, and what happens to it
A participant drops a term. The mentor puts it back.
board 1 · derivatives
f(x) = x² sin x
f′(x) = 2x cos x
both factors differentiated at once
f′(x) = 2x sin x + x² cos x
(u v)′ = u′v + u v′ : you kept only one of the two terms.
check at x = π∕2: 0 ≠ π
what the board sent · not a picture
- writing
- mentor · f(x) = x^2*sin(x)
- writing
- participant · f'(x) = 2x*cos(x)
- figure
- none
- intent
- grade
- units
- dimensionless, consistent
- recheck
- every numeric line is recomputed
Nothing here was inferred from pixels. The board sends what is written, line by line, with its author; homogeneity is checked before anything is sent, and every numeric line the mentor sends back is recomputed before the chalk touches the slate. That is why it can say which term is missing rather than that something looks wrong.
It doesn't look at your board. It reads it.
A tool that works from a screenshot is guessing. A screenshot has no exponents, no units, no vertices, only shapes that resemble them. Aptus is handed the state: what is written, how the figure was built, the vertex list of the solid. What follows is not interpretation, it is arithmetic.
The arithmetic is checked twice
The mentor recomputes what it is about to write, and corrects itself before the chalk touches the slate.
Diagrams work themselves out
A 3-4-5 triangle marks itself up: the right angle comes out of the figure, not out of an instruction.
What the board can do
Written mathematics
Fractions, exponents, roots, matrices, systems, units. You write, it sets itself.
Diagrams are computed, not drawn
Probability trees, Venn diagrams, the unit circle, graphs, circuits, inclined planes, pulleys, pendulums, lenses, refraction, thermodynamic cycles, waves, vector fields, energy chains.
Three dimensions
Solids computed by convex hull from their vertices, nets folded flat, plane sections with their nature written underneath, surfaces z = f(x, y), and molecules whose shape falls out of VSEPR theory.
The mentor
It corrects, explains, questions, marks. Its level is set class by class, and every participant has a ceiling.
The live room
The stroke reaches the participants while it is still being drawn. The voice follows. The instructor watches a wall of living boards, and hands over the chalk with one click.
Replay
A lesson is not a video, it is its own log. Play it back, jump from chapter to chapter, and ask a question pinned to the exact second.
Take the lesson with you
Export in the Aptus format, import it back somewhere else, print it to PDF. The lesson is yours.
Two languages, not a translation
English and French each exist in their own right, down to the way the mentor turns a sentence and the way numbers are written.
Around the board, a room
The stroke leaves before it is finished.
- The line reaches every participant as it is written, not once it is done. The voice follows it.
- The instructor sees a wall of live boards and hands over the chalk with one click.
- A session is not a video, it is its own log: replay it, jump from chapter to chapter, ask a question anchored to the second.
- A six hundred seat lecture hall and a phone on a bus watch the same stroke, at the same instant.
Your participants join with a code, with nothing to install.
Who writes on it
The same surface, whatever the room and whatever the screen.
Schools and colleges
One board per classroom, the same one at home in the evening.
Universities
Six hundred seats reading the same stroke, and the log of the session afterwards.
Training providers
Short cohorts, technical content, units that must not drift.
Companies
Internal teaching that has to be worked through, not slid past.
Independent instructors
One board, one link, no room to book.
Learners, on their own
Write your own line, and find out where it broke.
Where it comes from
The first board has left the prototype.
Aptus began as an object: a real board, in a real room, with chalk that leaves dust on your sleeve. Everything you have just read is its face at a distance, the same surface thrown onto as many screens as there are people, whatever their size.
No school has adopted it yet. That is the honest state of things, and it is why this page shows the board instead of describing it.
The board speaks two languages
Interface, chalk, mentor, exercises, worked answers: what you choose here holds everywhere, and follows you from one device to the next.
Open a board. Write one line.
Nothing to install, no slide deck to sit through. A blackboard opens, you write, and something reads it back.