Drill types
A drill is a short run of items, 8 to 15 in a planned session, 3 to 30 when you choose one yourself under Drills. Every item has exactly one focus skill, and the generator builds it so that the bead moves it needs use that skill’s rule and nothing you have not met yet. A “small friends” drill never asks for a carry; a “combined” drill always contains at least one combined move.
The item kinds
| Kind | You see | You do | Skills |
|---|---|---|---|
| Set this number | “Set 4071” and a clear soroban | Move the beads until they show it | S0 |
| Read this soroban | A number on the beads, digits hidden | Type the number | S0 |
| Chain | “6 + 5 + 6”, the start already on the beads | Work each operation on the beads | S1 to S9 |
| Multiplication | “34 × 6” | Type the product; the worked procedure is available | S10 |
| Division | “391 ÷ 17” | Type the quotient; the worked procedure is available | S11 |
| Anzan chain | A chain whose start fades from the beads | Finish in your head, type the total | A1 |
| Flash | Numbers shown one at a time | Type the sum | A2, A3 |
Working on the beads. For “set” and chain items you do not type the answer. The current operand is highlighted in the problem line; Abax follows the running total on the beads and accepts the item once the beads have shown the final answer for about half a second. You can also press Enter to check early (the Check button).
Hints. If you make no move for the hint delay (4 s by default, see Settings; 1.5 s in a lesson’s guided practice), the next move is shown on the soroban: the beads to move are haloed in vermilion, with an arrow, for one rod at a time.
When you are wrong. Abax shows the correct answer and replays the correct bead moves on the soroban in order, from where the item started. For multiplication and division the step-by-step procedure takes that role.
Where the drills come from
- A planned session (the Continue button on the home screen): warm-up, focus and cool-down drills chosen by the scheduler. About 30 % of the focus drill’s items are drawn from other skills you have already practised, each at its own current step.
- Drills on the home screen: choose a skill (grouped as set and read, add and subtract, longer numbers, multiply, divide, anzan), a step on its ladder (it starts at your current step; you can move it either way) and the number of items. Every skill can be chosen, whatever you have learned so far; it starts on the furthest skill you have met.
- Sprint: choose a skill and a step; you get as many items as you can answer in 60 seconds. Mistakes do not end it.
- Lessons end in three guided items (not recorded), then a 10-item drill.
Difficulty and time pressure
Each skill’s ladder (see the curriculum) raises one thing at a time: more operands, then more digits, then time pressure. Timed steps have a time budget per operand: 2.0 times your typical time on a “gentle” step, 1.3 times on a “tight” one, never below 1.2 s. The budget is not a countdown on the screen; the scheduler uses it to decide when you are fluent enough to go further: on a timed step you step up only when your typical time is at most 80 % of the budget.
Every answer and its time goes into the history and the scheduler, except in guided lesson practice.