Incredible app to learn the addition algorithm. It's designed by a teacher for teachers.

Addition Algorithm – Rigby Maths is an interactive app that teaches and reinforces the standard written (column) addition algorithm. Learners build answers one column at a time—focusing on place value, accuracy, and the correct method—so they don’t just “get the answer”, they understand how the answer is made. Across five levels, the difficulty grows from first-time algorithm practice, to carrying (regrouping/renaming), to larger place values, adding three numbers, and finally working with decimals (tenths and hundredths).

The app includes guided “Learn” tutorials and an on-demand help feature with clear voice prompts, plus optional visual supports like a carry helper overlay, tens frames, and visual dots to make the maths more concrete. Progress is tracked with a mastery percentage per level, and the question wording is customisable—choose whether the app says “add” or “plus”, and whether it uses “carrying”, “renaming”, or “regrouping” to match what learners hear in class. It’s useful for independent practice at home and structured practice in schools, giving students confidence with the algorithm while giving adults a simple way to see steady improvement over time.