STEM AND ASSESSMENT EVIDENCE WORKBENCH
Preserve a written decimal, decompose every digit into a signed power-of-ten contribution, and compare place-value claims visibly.
Review output
Load the worked example to inspect realistic inputs, or enter anonymous classroom or laboratory evidence. Results remain in this browser tab until you copy or download them.
Transparent method
A digit at power p contributes digit times 10 raised to p. Positions left of ones have nonnegative powers; positions right of the decimal point begin at negative one. For a negative value, the sign applies to every nonzero contribution. Summing the signed contributions reconstructs the numeric value while the original string preserves written zero placeholders. A supported claim identifies the digit occupying the named place in the entered notation. The contribution table shows what that digit means relative to the declared whole. A zero digit still holds a position even though its additive contribution is zero. Follow the symbolic table with an equal-sized grid or number-line model and ask the learner to name the unit whole.
Confirm the prompt, approved source, units, symbols, notation, expected model, and review threshold. Keep an unchanged copy of observations or learner responses before editing any row.
Run the worked example, inspect intermediate rows, and compare the evidence with a hand calculation, diagram, physical model, periodic table, or moderated assessment source.
Record the method, assumptions, units, classifications, rounding, and flagged rows. Treat the downloaded report as editable evidence and verify it independently before instruction or assessment.
How to interpret the result
Use when learners need to connect decimal notation with powers of ten, expanded form, base-ten blocks, grids, money, measurement, or a number line. The builder preserves trailing zeros as written evidence. It does not decide whether those zeros are significant figures, draw physically measured blocks, infer the intended whole, round values, or diagnose conceptual understanding from one digit claim.
The value 304.5070 keeps seven visible places: three hundreds, zero tens, four ones, five tenths, zero hundredths, seven thousandths, and zero ten-thousandths. Six entered claims match. The final claim says the ten-thousandths digit is one, so the report points back to its zero contribution without removing the trailing zero from the original notation.
A digit at power p contributes digit times 10 raised to p. Positions left of ones have nonnegative powers; positions right of the decimal point begin at negative one. For a negative value, the sign applies to every nonzero contribution. Summing the signed contributions reconstructs the numeric value while the original string preserves written zero placeholders.
A supported claim identifies the digit occupying the named place in the entered notation. The contribution table shows what that digit means relative to the declared whole. A zero digit still holds a position even though its additive contribution is zero. Follow the symbolic table with an equal-sized grid or number-line model and ask the learner to name the unit whole.
Do not count the decimal point as a place, rename tenths as tens, drop internal zeros, assume more decimal digits always mean a larger value, or change the unit whole between models. Do not treat a trailing zero as mathematically changing the value, while also avoiding removal when it records measurement precision required by the context.
Learning boundary
This browser-local workbench applies only the disclosed model to entered values. It cannot diagnose a learner, certify an experiment, establish a chemical fact, classify a task automatically, or replace teacher and laboratory judgment.
Review checklist
Practical questions
No. Processing occurs in the current browser tab. Avoid names and other personal information, and retain authoritative records only in the system approved by the school.
No. It reports how the entered evidence behaves under one disclosed rule. Ask for reasoning and compare several evidence sources before reaching an educational conclusion.
Treat it as an editable calculation aid. Show your own reasoning, cite required sources, use the course method, and follow the applicable academic-integrity rules.
YOUR NIRMION
