# SSDD Problems: 10 tips to supercharge them in the classroom

### Ideas to improve one of my favourite task structures

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Welcome to a series of posts where I will share 10 ideas to supercharge some of my favourite student practice activities. We will cover:

SSDD Problems (this post)

Intelligent Practice

A little bit of problem-solving in each lesson

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### SSDD Problems

Everyone loves an SSDD Problem. Heck, I love them so much that I built a website full of them. Here is one of my favourites:

### The basic idea

SSDD stands for *Same Surface, Different Depth*. They are a special set of problems that may look similar at first glance, but require different mathematical ideas to solve them.

### Why SSDD Problems are a good idea

SSDD Problems are one of the best ways I know of to tap into the power of *interleaving*. Interleaved practice involves mixing up the concepts involved instead of having students practice the same skills over and over. Interleaving is thought to improve learning via three explanatory mechanisms, each of which is turned up to the max with a set of SSDD Problems:

*Retrieval practice*- instead of having to retrieve one idea, students need to retrieve four different ideas. Each act of retrieval strengthens that memory.*Attention attenuation*- students have to pay more attention when topics are constantly switching than they would have to do if the practice focused on just one idea.*Discriminative constant*- this is the big one. Because each set of SSDD Problems has a surface feature in common (an image, a number, a context), students must think hard about how to identify the relevant deep structure so they can figure out what strategy to use to solve the problem.

Consider the set of SSDD Problems above. Students have the opportunity to retrieve the area of a triangle, forming and solving equations, angle facts, and Pythagoras’ theorem. They also have to be on the ball when working through each problem, constantly switching topics and strategies. Finally, students are forced to ask themselves, for example, why do the top-left and bottom-right questions require different strategies, even though they both have an isosceles triangle and ask for the area?

You can listen to me discuss interleaving, along with other desirable difficulties, with researcher Nick Soderstrom here.

### SSDD Problems: 10 top tips

With any new activity structure, lowering the content demands initially is important to help students get familiar with the structure and ensure that their first experience is a positive one. This is particularly true in the case of SSDD Problems which can seem both weird and impenetrable, thus causing students to down tools before they have even started. Beginning with a relatively simple set of four questions should help students get used to the format, and build up the foundation of success needed for when the content demands increase.

Just like with Venn Diagrams, I like to ask students to work using my

**4-2 approach**. This is where students work on their own, in silence, for 4 minutes, and then have 2 minutes of collaboration with their partner, before the cycle repeats. I find 4 minutes is sufficient time for students to do some thinking on their own without being dominated by an eager partner, and 2 minutes is sufficiently short for the students to have a positive, focused paired discussion to compare their answers and their thinking.If you are feeling brave, I have seen SSDD problems work well as group work tasks, with each member of the group taking responsibility for one question, and the other members checking their work and offering help when needed:

As ever, the key to successful group work is making sure all members of the group pull their weight and have an opportunity to think hard about all four questions, and not just their own. You can listen to me discuss how to make group work effective with Sammy Kempner here.

Explicitly tell students that they can start on any question they like. This may be obvious to us, but countless times I have seen students spending all their time on the top-left question assuming they are not allowed to move on until they have completed it.

If creating your own set of SSDD Problems (or editing an existing set), ensure the top-left question is the most accessible, because even though you tell students to start anywhere, everyone will begin with the top-left and you want students to get off to a good start.

If students get really stuck on a question, ask them to write down what topic it is. This stops students from thinking that if they cannot answer the question then there is no point in them writing anything, and also gives you valuable insight as to whether strategy selection is the issue, or if the problem lies with carrying out a procedure.

If a student finishes early, a nice challenge is to ask them to create a 5th question for the set, complete with working out and answer. They can then give this to another student who has finished.

SSDD Problems work particularly well as mixed-topic starters. As I have previously written about, four questions is a good number for the Do Now, and you get all the benefits of retrieval, attention attenuation and discriminative contrast discussed above.

I also like to use SSDD Problems to practice high-value skills. So, you could give students a set of problems like this on a Monday:

And then on Tuesday give the same set of questions but either change the 5 to a different integer, or change the multiplication sign to a different operation.

SSDD Problems work really well as revision activities in the build-up to GCSE exams. Again, the benefits of retrieval, attention attenuation and discriminative contrast are exactly what is needed when taking on an unpredictable assessment. A diet of one or two SSDD Problems in the months leading up to GCSEs might just do the trick.

### Three of my favourite SSDD Problems

Challenge your students with some of these… or enjoy trying them yourself. And remember, you can find all my SSDD Problem activities here.

Applications of fractions:

Skills with coordinates:

Thinking hard about ratio:

What is your experience with SSDD Problems?

Do you like any of these ideas?

Do you have any extra tips to share?

Let me know in the comments below!

**🏃🏻♂️ Before you go, have you…🏃🏻♂️**

… checked out our incredible, brand-new, free resources from Eedi?

… read my latest Tips for Teachers newsletter about putting mini-whiteboards together?

… listened to my most recent podcast about feedback cycles, lesson observations and Exit Tickets?

… considered booking some CPD, coaching, or maths departmental support?

… read my Tips for Teachers book?

Thanks so much for reading and have a great week!

Craig