I was introduced to lock box challenges a few years ago by a colleague and must say that I just LOVED the idea! It was so simple and so brilliant and the students absolutely love it. Now get me wrong, it is definintely a bit of a gimic, but there is something really nice about watching students become so engaged in an activity all in the name of a prize. It is definitely a great way to engage students with revision.

If you are not sure what a lock box is, a photo of mine is below:

This really is what it says on the tin. I bought a nice looking box (I think this one was from the works and was under £5) and then attached a combination lock (mine is 4 digits. Make sure you know how your lock works so you can change combinations easily. I have a basic code that I always set my lock back to so that I can always get into my box). My box is filled with lollies but you could put in what you want. You don’t have to give out sweets, you could place cards in that specify a certain amount of house points etc it is entirely up to you. Once you have these things, you can change each challenge easily.

For the lock box challenge I used today with my year 7s, I created a challenge to aid revision. So I created a table that had 8 rows and 2 columns. One column had the letters A to H, and the other had the questions in that the students had to answer. In pairs, they then had to work throguh the 8 questions and get a value for each letter. Once they had done that, they were then asked to put those values into an expression which would then produce a 4 digit number. This 4 digit number is the code to the lockbox. Really easy for students to know if they are wrong or right; 1) If they don’t get a 4 digit code from the expression then they have either made a mistake in the original 8 questions or made a mistake when substituting into the expression 2) the box won’t open. If either of these 2 things happen, then back to the drawing board. I have one very basic rule in my classroom with lockboxes: Mrs Mahoney is not helping until you have attempted to get the 4 digit code. If they don’t open the box after an attempt, then I aid them my marking their 8 questions. They then know if it is an error with this part or with the substiution.

The lock box challenge is pretty easy to make easier if required. In the past instead of giving the students an expression to substitute into, I told them to add up their 8 answers instead. If this wasn’t going to produce a 4 digit code then I would instruct them to add up their 8 answers and then add on a set amount that I then know would come to a 4 digit number.

I would recommend using a count down of some kind so that the activity does have a clear end point. I then also tend to cut off students joining the queue waiting to try their code at about 1 minute left. It just makes it very clear to all students where the end is, otherwise you find your queue never seems to disappear.

The students genuinely do love this activity. I don’t use it all the time but I do like to include a different activity each term where I can. There are some books out there that have pre-made padlock challenges: https://www.amazon.co.uk/Padlock-Challenges-using-Number-Algebra/dp/0906588790 I do have this book but I haven’t actually used the activities from it yet. The book did come with a CD ROM with the pages on so it is very easy to print off. The intention of the book is that you put a few of their activites together and create a booklet of their challenges to produce a final code.

The challenge I used today is here:End of year revision lockbox challenge number

I printed page 1 several times over and gave each student a challenge (they worked In pairs and did their working out on whiteboards). I then projected the expression onto the board for the duration of the activity. Then at the end I went through the answers and revealed the code. I did have several pairs break into my box.

If printing budgets are tight, I have projected the question table onto the board before (In smart notebook so I could also use the timer) and then wrote the expression onto my non interactive whiteboard.

Whatever you want to do, whether it is create your own challenge or use ready made ones, I would encourage you to give this activity a try.