This printable worksheet may be useful: Number Daisy.
Why do this problem?
This problem builds fluency in numerical manipulation and encourages independent investigation and systematic working. The activity is very accessible but leads into interesting questions about number properties and number bonds.
You could explain the concept of a Number Daisy and demonstrate how to find a selection of numbers using the daisy. Working in pairs or individually, the students could then find the remaining totals to check that the numbers 1 to 25 really can all be made.
Using mini-whiteboards and squared paper (to allow students to draw a table to record their results systematically) might be useful in this activity. Let students choose numbers and arrange them on their daisies. Challenge them to find a daisy that can make the most numbers.
Allow groups to check each others’ daisies and give them time to describe their strategies. Towards the end, have a class discussion to exchange ideas and strategies, and to see who in the class got the highest total.
How can we record our findings?
Are there some numbers you will always need?
Are some numbers more useful than others?
What do you notice about the number that is in the middle of the daisy?
Why is the layout of the numbers important?
You could start by only using numbers between 1 and 9.
You could relax the rule that only neighbouring numbers can be added.
What happens if we change the layout of the numbers?
What happens if we have a different number of petals?
What happens if we are allowed to subtract as well as add?