Wishball challenge: tens

TLF ID L8459

Challenge your understanding of place value in whole numbers up to 99. Receive a starting number, such as 86, and work towards turning it into a target number, such as 18, within 20 turns. Spin a random digit, choose its decimal place value and use the given operation (either addition or subtraction) on your starting number. Be careful not to undershoot the target number! Use the ‘Wishball’ to select your final digit. Try to achieve the target in as few turns as possible. This learning object is one of a series of 15 objects.

Educational details

Key learning objectives
  • Students identify the place value of each digit in two-digit numbers.
  • Students add and subtract ones and tens in two-digit numbers.
  • Students read and interpret different representations of numbers.
  • Students apply mental computation skills.
Educational value
  • Develops students’ understanding of place value.
  • Stimulates students’ mental calculation strategies.
  • Uses three different methods of representing numbers to assist students’ visualisation of place value.
  • Scaffolds students’ attempts with immediate feedback.
  • Encourages repeated use through randomisation of activity elements.
  • Includes an option to print a record of the place-value decisions made for every turn in each game.
  • Includes voiceover support for key instructions.
Year level


Learning area
  • mathematics
  • Mathematics/Number and algebra
  • Mathematics/Number and algebra
    Student activity
    • Interactives;
    • Games;
    • Experiment;
    • Analysis;
    • Modelling

    Other details

    • Technical implementer
    • Script writer
    • Name: Michael Wagner
    • Organisation: Godwin + Wagner
    • Address: Box Hill South VIC Australia
    • Subject matter expert
    • Name: John Flatt
    • Address: Geelong VIC Australia
    • Subject matter expert
    • Name: Howard Reeves
    • Address: Lindisfarne TAS Australia
    • Technical implementer
    • Publisher
    • Date of contribution: 20 Sep 2013
    • Organisation: Education Services Australia
    • Address: Melbourne VIC Australia
    • URL: http://www.esa.edu.au/
    Access profile
    • Colour independence
    • Device independence
    • Hearing independence
    Learning resource type
    • Tablet friendly (Interactive resource)
    • any - minimum version: Microsoft Edge (Windows); Default Android Browser
    • Google Chrome - minimum version: 35+ (Windows, macOS, Android)
    • Firefox - minimum version: 45+ (Windows & Mac)
    • ms-internet explorer - minimum version: 10+ (Windows)
    • Safari - minimum version: 7+ (Mac); Safari for iOS 9+ (iOS)
    Operating systems
    • ms-windows - minimum version: Vista+
    • macos - minimum version: 10.9+
    • ios - minimum version: 9+
    • android - minimum version: 5+
    Platform requirements
    • Due to the use of rich media content, this learning object is suitable for a connection speed of 256kb/s or faster.
    • © Education Services Australia Ltd, 2016, except where indicated under Acknowledgements. Unless otherwise indicated, this material may be used in accordance with the Creative Commons Attribution 4.0 International (CC BY 4.0) licence creativecommons.org/licenses/by/4.0/.