Read each expression as a structure. Select the operation whose complete subexpression should be evaluated next, inspect its registered model, then reduce exactly one stage.
Three modes
- Predict: decide which operation is first, Check it, inspect the model and reduce that one stage.
- Step: select, Check, calculate the selected part and Reduce until one value remains.
- Compare: complete otherwise identical expressions with and without brackets, then compare what changed.
The structural rules
Work inside brackets first, then evaluate small powers. Multiplication and division share one priority tier, so work from left to right between them. Addition and subtraction also share one tier and are worked from left to right. The mnemonic does not mean division always comes before multiplication or addition always comes before subtraction.
Support and feedback
BIDMAS shows a child-friendly guide whenever you are choosing the next operation. It keeps division with multiplication and addition with subtraction, because each pair has the same priority and is worked from left to right. The guide does not mark the answer. Hint first names the structural tier, then outlines all operators in that tier. Check checks the current selection or value. Reveal resolves only the current decision. Reduce remains a separate one-stage action.
Starting again
Clear removes only current-stage pupil work. Reset restores the same starting expression and keeps teacher choices. New creates an unseen task under the same choices. Restore defaults resets the teacher choices.
Use Tab to reach operators and the arrow keys to move between them. Whole-number answers accept an ordinary keyboard; on a touch display, tap the input deliberately to open the shared number pad.
Printing for teaching
The header Print control prints the current display. Print Worksheet opens the protected teacher resource builder for teaching examples, practice, bracket comparison, misconception work, BIDMAS support, exit checks and a complete lesson pack.
