Teaching and Group Activities for Understanding
Use large pieces of A1 paper, with one cut into 10 equal strips to model 1s and 0.1s. Demonstrate that if a child is holding 1 strip, they have one tenth or 0.1. Repeat for 4 strips and 8 strips. Show that if a child is holding one whole piece of paper and 3 strips or tenths, they have 1.3, etc. Record different decimal numbers.
-- Cut paper to make tenths. Use to play a game counting on in tenths to make 1s and 0.1s.
Launch the ITP ‘Moving digits’. Click, then drag cards to make the number 56. Click on ÷ 10. Discuss the place value of each digit, explaining that the 6 is now ‘six tenths’. Point out that we can also write this as zero point 6, 0.6. Repeat, dividing other numbers by 10 to derive 1-place decimals, e.g. 27, 49, 435, 409, 40, 4.
Use the in-depth problem-solving investigation ‘Magical square decimals’ as today’s group activity.
Or, use these activities:
-- Move digit cards on a place value grid to divide 2-digit numbers by 10.
-- Create 2-digit numbers and divide them by 10. Write a generalisation.
Draw a large decimal point on a flipchart. Ask 2 children to stand either side holding large digit cards, e.g. 2 and 5 to show 2.5. Ask children to discuss in pairs what each child will need to do if we multiply 2.5 by 10. Model this, showing that 2.5 × 10 = 25 as both digits move one place value column to the left. Repeat for other numbers.
-- Use a ‘function machine’ to multiply and divide numbers by 10.
-- Play bingo to practise multiplication and division of numbers by 10.