Class 5: Mission mathematics

Ideas to practise

• Working backwards. Undo the last operation first, then undo the earlier operation.
• Equal groups and multi-step problems. Find the total in equal groups before applying the next change.
• Equal sharing. Divide into equal groups. Check by multiplying your answer by the number of groups.
• Addition and missing amounts. Combine the amounts, or work backwards from the total.
• Factors and multiples. Factors divide an amount exactly; multiples are repeated totals. Choose which idea the situation needs.

A game mission has 8 untimed questions. Only the game saves choices and hints. A finished mission earns one launch charge and participation towards the Propulsion cluster in Galaxy Command. The chapter goal is 8 different questions in finished sets; hints and wrong answers count as participation, not mastery. Some craft systems link more than one chapter.

Choose a level

Levels change representations, clues and conditions, not just the numbers. These are practice formats, not validated exam-equivalent difficulty.

Using the feedback

Learning reports distinguish hinted answers from independent first choices. They consider up to 20 recent different, unhinted questions per skill and level, and wait for at least five before suggesting extra practice. Repeating the same question does not add evidence. Reports are practice evidence, not IQ scores, diagnoses, ranks or predictions of competition results.

Ask the learner to explain a drawing or check with objects too. Choose Explore or an earlier chapter when a step feels too large.

Sources & limits

The grade topics use SOF IMO Class 5 published topic syllabus as their primary reference. The SOF sample and CREST previous-year paper below informed representations and reasoning demands. Providers have different topic boundaries; their syllabi are not interchangeable.

• Sample, not an administered paper: SOF IMO Class 5 sample, 2026-27
• Previous-year paper: CREST CMO Class 5 previous-year paper, 2023-24 Set A

Questions, diagrams, picture choices, hints and explanations are original Otterly work, not copied paper questions or publisher artwork. No Olympiad provider is affiliated with or endorses Space Academy. This is not complete exam preparation; follow classroom teaching and check the current official syllabus too. Independent educator review is still needed for difficulty and breadth.

Content and coverage notes. To report a confusing question, describe the grade, chapter, level and question on the contact page. Do not send children’s personal information.

Private, local saves

Game progress stays only in this browser, in three anonymous explorer slots. Clearing site data or closing a private session may remove it. Download a private backup from Help & saves; there is no cloud sync. The game checks saves before play and stops on save failures rather than pretending progress was saved.

These page examples never change a saved game. Game links carry question settings, not a learner’s answers. There are no names, school details, public profiles, chat, analytics or advertising SDKs in the game. Grown-up guidance · Privacy