Wishball
The Wishball series of learning objects encourages thinking about place value. It also provides opportunities for mental addition and subtraction.

wishball

Learning objects
LO ID
Years
Wishball: whole numbers
867
3-4
Wishball: tenths
868
4-5
Wishball: hundredths
869
5-6
Wishball: thousandths
495
5-6
Wishball: ultimate
870
6
Wishball challenge: whole numbers
871
3-4
Wishball challenge: tenths
872
4-5
Wishball challenge: hundredths
873
5-6
Wishball challenge: thousandths
874
5-6
Wishball challenge: ultimate
875
6

Students try to reach a target number by adding or subtracting in fewer than 20 moves. The Spinner randomly serves up a digit. Before students add or subtract they first choose a place value to assign to the digit. So, if 2 is the digit served up, students can make it 2.0, 0.2, 0.02 or 0.002. Students may also refer to the number line or counting frame to help confirm the soundness or otherwise of their computations. The Wishball option, which can be used only once, allows the students to choose the digit required to finish the game. With feedback, students are challenged to develop more effective problem-solving strategies in an effort to achieve the target.

The Wishball series of learning objects comprises two subseries: Wishball and Wishball challenge. In both subseries the decimal point is placed so students can explore whole numbers, tenths, hundredths or thousandths. The ‘Ultimate’ versions offer random placement of the decimal point.

Both the addition (+) and subtraction (–) operators are provided for students to use for calculation. In ‘Wishball challenge’ students are randomly offered either the subtraction or addition operator to make their calculation.

By using the range of learning objects in this series, students realise that the same strategies for calculation apply regardless of where the decimal point is placed.