Investigate how you can work out what day of the week your birthday will be on next year, and the year after...
Label this plum tree graph to make it totally magic!
Find all the ways of placing the numbers 1 to 9 on a W shape, with 3 numbers on each leg, so that each set of 3 numbers has the same total.
Start with a formula that has only multiples of n, nothing added or subtracted, for example : $2n$, $3n$, $4n$ or $5n$
Look at the sequence of blue numbers and notice the pattern - explain why it happens.
When you can explain what happens, switch to a formula where something is subtracted.
Interactive Number Patterns 2
Do you see a connection between Difference 2 and the formula? Change the formula to check that you were right about the connection.
Finally, use those numbers in the bottom half of the screen to help you explain why the connection you discovered in Difference 2 actually works.