I’ve written a lot about great teaching ideas or great assessment ideas that I’ve seen in action when visiting school and teachers. This term I have been visiting my training teachers in their placement schools and stumbled across a fantastic idea for teaching formulae. Allow me to introduce the formula bucket.

Trainee teachers have both the benefit and the curse of taking over a class where another teacher has already established the routines. One group I observed recently had established some really remarkable habits, and one of them was their formula bucket, which they used to learn and revise formulae.

## How the formula bucket works

Each table in the class had a bucket, and in each bucket were numerous cards in two colours, eg green and yellow. On the green cards were terms such as ‘d’, ‘r’ or ‘Area of triangle’, and on yellow cards were operators such as ‘+’ or ‘-‘.

One of the students explained to me, “Each time we meet a new formula we put it in our bucket.”

She shuffled about in the bucket and pulled out the cards saying: ‘Area of a circle’, ‘=’, ‘π’ and ‘r^{2}’.

“When we did circles we put these in.”

The student continued: “If we can’t remember a formula we can use the bucket to try to work it out.”

The students are allowed to empty out the contents of the formula bucket at any time during a lesson, and sort through the cards to find the formula they need – this might mean setting out the formula they already know, and assembling the one they need reminding of with the cards that are left.

The magic of the formula bucket is that by searching for the formula they need at that time, they are refreshing all the other formulae at the same time.

Each time the class learns a new formula, they put more cards in the bucket. By the end of year 11 they’ll have all the formulae that they need to know for their exams.

The class teacher had a bucket for each table in the class. You might be wondering how she had time to make all the cards for each bucket in each class, but she explained that she gets the students to make the cards themselves.

“Whenever we learn a new formula, the pupils come and get the right number of cards from me, write out the parts of the formula on separate cards and put them in the bucket.”

## An exercise using the formula buckets

The class teacher also told me about a game she plays with the students, using the formula buckets to help them remember formulae.

“Every Friday, I walk round the tables and take out one card from each bucket, without telling the students which card it is.

“The students then have to work out which card I’ve taken, by assembling the cards that are left in the bucket into formulae and working out which part is missing from which formula.

“It only takes about five minutes, but the students love it.”

I think it’s a great way to help students revise the formulae they need to know for exams.