Ip Dip
"Ip dip sky blue! Who's 'it'? It's you!" Where would you position yourself so that you are 'it' if there are two players? Three players ...?
Age
5 to 11
Challenge level
"Ip dip sky blue! Who's 'it'? It's you!"
Have you ever used this rhyme to decide who is 'it' in a game?
If you were playing a game with one friend and you wanted to be chosen to be 'it', would you start the rhyme pointing at yourself or your friend?
If there were three of you, how would you position yourself so that you were sure you'd be chosen?
How about with four of you? Five ...? Six ...? Seven ...? Eight ...? Nine ...? Ten ...? And so on?
How would you predict where you should stand to be chosen for any number of players?
How will you remember who is 'it' for different numbers of people?
You could use something like counters or cubes to represent people.
We had lots of solutions sent in for this activity. Brookfield Junior School obviously got very involved and sent in many solutions. Here is an example of two of them.
Firstly, from Bill:
The formula to Ip dip is n≥8 when n stands for the number of friends so that means if the number of friends is eight or over you should be in the eighth position. To solve the first bit the position is the remainder of the number of the friends divided by eight. so the formula is p=8/n= the remainder.
Secondly from Tomas:
If you had two people you would start in second position.
If you had three people you would start in second position.
If you had four people you would start in fourth position.
If you had five people you would start in third position.
If you had six people you would start in second position.
If you had seven people you would start in first position.
If you had eight people you would start in second position and so on.
From Mossley Primary School we had solutions sent in from Kati-leigh, Luke, Chiara, Amelia and Emily. Here is one example:
2: start with friend
3: right friend clockwise
4: second to right clockwise
5: third to right clockwise
6: left clockwise
7: yourself
8: right clockwise
9: second to right clockwise
10: third to right clockwise
11: third to left
Thanks for reading.
Amelia and Bea from Barton C E V A Primary School sent in the following
If there were 8 or more players, then always go for the 8th place.
If there were fewer than 8 players then you would find how many players there are and see what number adds to the amount of players to get to 8.You may need to use multiplication facts with this:
7 players: 1x7= 7 7 + 1 = 8 You go in 1st place
6 players: 1x6= 6 6 + 2 = 8 You go in 2nd place
5 players: 1x5= 5 5 + 3 = 8 You go in 3rd place
4 players: 1x4= 4 4 + 4 = 8 You go in 4th place
3 players: 2x3= 6 6 + 2 = 8 You go in 2nd place
2 players: 3x2 = 6 6 +2 = 8 You go in 2nd place
This is because there are 8 words in the rhyme.
Thank you, all of you, for the ideas you sent in, in order to solve this challenge.
Why do this problem?
This problem offers the opportunity for children to work on some mathematics that might be meaningful to them, and therefore engaging. At a basic level, it involves counting, but it is a good context in which children can be encouraged to identify and explain patterns using their knowledge of factors and remainders.
Possible approach
You could start by having a pair of volunteers standing up together so that everyone can see them. Ask the children to imagine that they are going to play a game of tag, or something similar. How would they choose who was going to be 'it' i.e. the person to do the chasing? Take some suggestions, which might involve some rhymes that are currently popular. You could choose to
go with one of these, or introduce the "Ip dip ..." rhyme with which some might already be familiar. (The important point at this stage is that the rhyme identifies the person to be 'it' straight away, having said it only once.)
Say the chosen rhyme together a few times so that everyone feels they know it well and then indicate that you're going to find out who is going to be 'it' from the two volunteers. Say the rhyme while pointing to the children alternately. You could then pose the question about who you would start the rhyme on if you wanted to be chosen. Give the whole group a chance to
talk in pairs about this, then test out their ideas. You can then encourage pairs to work together to discover where you would position yourself if there were three of you ... four ... five etc.
It may be appropriate to stop everyone after some time to share ideas so far. This might involve some pairs explaining how they are approaching the problem and sharing some possible ways of recording what they're doing.
In the plenary, you can agree on solutions for the different numbers of people but also encourage children to talk about what they notice and to explain why where possible. How could they predict where to stand if there were seven people, for example, or ten people or a hundred people? Some might find it tricky to articulate where to stand for fewer than eight people, but a few
demonstrations with larger numbers will mean they are able to explain where to be for eight or more relatively easily. Can they tell you why eight is the 'key' number?
Key questions
What numbers of people have you tried? What did you find out?
How are you going about this problem? Tell me what you've done.
How will you remember what you've found out?
Do you notice any patterns?
Can you explain the patterns?
Possible extension
Some children may like to try with another version of this rhyme which makes the analysis much more tricky: "Ip dip sky blue! Who's 'it'? Not you!" so that a person is 'knocked out' each time and the only person left is 'it'. What happens when there are two people? Three? Four etc? Can they see any patterns emerging? Can they explain why the
patterns occur? Similarly, learners might like to test out the best places to be positioned for a rhyme of their choice.
Possible support
Having counters or other objects available to represent people might help some children.