I love this site as it's a fantastic way to get the kids applying their mathematical knowledge. The Leaderboard introduces an element of competition and the problems change each time the game is played so pupils cant just learn the answers. If you set up a class account you can keep track of what the pupils have attempted and how well they did - so you can target problems straight away.
I remember taking ages to create a 'salade de mots' of words for A level topics. Wordle does it for everything & you just paste all the words into it and creates 'wordles'. Apologies if you knew about this.