Brills are the rewards with which we incentivise players to play and learn. Amazingly, provided you are a subscriber, you can cash them in for … cash!

Whenever you play a brick, your percentage converts into brills, so 79% would earn you 79 brills. If you then replay a brick and improve, you earn additional brills - 85% on the same brick would earn 6 more brills.

However, you need to score 50% or more to earn brills, and if you get 100% you will get a substantial bonus depending on the length and difficulty of the brick.

The most exciting thing about brills is that you can win them in vast amounts playing competition bricks. Not only do you earn double brills, but there is an additional prize pot spread across the top scorers.

For competitions, there will be always be a prize pot of a few hundred brills even if there are only a few players: if there are hundreds of players, the prize pot rises to thousands of brills. We want to create brillionaires!

• 3,000 brills enables you either to gift a subscription to someone else, or to upgrade from a [basic] subscription to a [premium] subscription.
• 5,000 brills enables you to either to purchase a subscription or to cash in £25 (or exchange rate equivalent in another currency). You can also renew a [basic] subscription for 5,000 brills.
• 10,000 brills enables you to cash in £75.
• 20,000 brills enables you to cash in £200.

Brills are the rewards with which we incentivise players to play and learn. When you reach one of the thresholds above you get a notification asking whether you want to exchange your brills or keep them for the time being. If you want to exchange, the brills are credited to the card with which you set up your account. But you will need to take a selfie with the prize notification - this helps our marketing and it also proves that the prizes are real.

If you use Brillder by buying credits or on a basic five credit pcm subscription, you may sometimes run out of credits. In this event, you can actually cash in your brills in exchange for brick credits - a catalogue brick costs 100 credits to play, while a competition brick costs 200.

Yes - many teachers use Brillder to create and store self-marking resources for their students to play. The build function is intuitive and easy to use. You can access it by selecting “teacher” on your profile.

Of the bricks on our system are invisible because they are built and assigned for ‘personal’ use by teachers. (These can be shared with colleagues but are not published more widely.)

Some teachers contact us if they think they’ve written a really good brick which might be considered for the public catalogue. We are willing to buy bricks (usually for around £100) if we think they would complement the catalogue. Once you are an author, you also have a claim to a proportion of downstream revenue which your brick(s) may earn.

We will always reply to an application, but our public archive contains only bricks which have been peer-reviewed by another subject specialist (appointed by us), so there may be an interval while we look at what you have done. We have a 1-10 grading system, with 10 being publishable standard. Most bricks submitted are level 6 or below, and therefore rejected, but our editors work with those rated 7,8 and 9 to create publishable bricks, and those capable of creating bricks consistently to 8+ standard may be invited to become regular authors.

Yes, you can take a public catalogue brick and add questions, remove questions, add notes to the synthesis or links to the preparation. That adapted brick then becomes personal to you - obviously, the public catalogue original remains unchanged.