SPACE ACADEMY · TRY, THINK, PLAY

Class 2: Space supplies

Use pictured values and price boards to compare purchases, change and budgets.

Try a quick challenge

Just a quick try. Not saved; no game rewards.

ExploreMoney and change

A shopper buys 3 erasers and 3 pens at the prices shown and pays Rs 60. How many rupees change?

sharpenerRs 8eraserRs 5penRs 10
  1. 15
  2. 105
  3. 25
  4. 45
Need a hint?

Find the total cost first. Then take it away from the money paid.

Answer & method
Answer A: 15

The total is 15 + 30 = 45. Change: 60 - 45 = 15 rupees.

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ReasonMoney and change

A shopper buys 2 rulers and 3 erasers at the prices shown and pays Rs 60. How many rupees change?

eraserRs 2pencilRs 5rulerRs 15
  1. 36
  2. 14
  3. 24
  4. 96
Need a hint?

Find the total cost first. Then take it away from the money paid.

Answer & method
Answer C: 24

The total is 30 + 6 = 36. Change: 60 - 36 = 24 rupees.

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StretchMoney and change

Look at the two shop deals. How many rupees do you SAVE buying 10 battery cells in packs instead of singles?

Single Price1 itemRs 9Pack DealPack of 5Rs 39
  1. 30
  2. 90
  3. 6
  4. 12
Need a hint?

Find the cost of buying that many singles one by one, then subtract the pack price.

Answer & method
Answer D: 12

Buying 10 singles costs 10 x Rs 9 = Rs 90. Buying 2 packs costs Rs 78. You save Rs 90 - Rs 78 = Rs 12.

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For grown-ups

Ideas to practise

  • Money and change. Find the total cost first, then subtract it from the amount paid.

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 Left solar panel in Outer Planet Voyager. 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

Explore

Foundations: read a representation and practise the underlying idea.

  • Combine pictured coin values
  • Total or change from price tags
  • Spot the wrong way to write an amount
  • Pick the purse that shows an exact rupee amount
  • Pick two shop items that match an exact total
  • Track rupees saved and spent in a story
  • Find a missing item price on a receipt
Play Explore

Reason

Paper-style reasoning: connect clues, interpret a diagram or work backwards.

  • Find change after a linked purchase
  • Total or change from price tags
  • Spot the wrong way to write an amount
  • Find a missing item price on a receipt
  • Compare pack deals to find the cheaper buy
  • Track rupees saved and spent in a story
  • Pick two shop items that match an exact total
Play Reason

Stretch

Higher-order practice: link conditions, test statements and avoid a tempting wrong method.

  • Choose a purchase satisfying a budget condition
  • Total or change from price tags
  • Spot the wrong way to write an amount
  • Pick the purse that shows an exact rupee amount
  • Find a missing item price on a receipt
  • Compare pack deals to find the cheaper buy
  • Pick two shop items that match an exact total
Play Stretch

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 2 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.

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.

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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

Original Otterly practice, not an official exam. Game progress stays on this browser.