It's meant to be a game where you are given a pixelated sprite and you have to guess what it is. If you get it right, it's meant to say 'Congratulations! Your score is ' and move on to the next level. And if you get it wrong, you lose 20 points and the answer disappears. It works fine for level 1, but then it goes glitchy…

I've kept all the variables shown, but usually they would be hidden.

http://scratch.mit.edu.ezproxyberklee.flo.org/projects/11257453/

Nowhere in your scripts is there a “next question”. The first question is asked then the script ends. You do broadcast a next level but all that does is change the backdrop.

Ok just seen the easy, medium broadcasts that do provide another question. Guessing its a timing issue. You're mixing broadcasts and setting and checking variables. It would help if you stuck with variavbles or broadcasts to synchronise events.