Great idea (and a great source for inspiration!), but a but hard to take seriously, when the very first part contains the passage "Uranium isotope 235 (meaning it contains 235 neutrons)". No, no it does not. It means it has a mass number of 235, in this case from 92 protons and 143 neutrons.
I get it, it's easy to make mistakes, but if you want people to use this as a learning tool, you _need_ to check and double check statements.
Still, an amazing idea, and I hope you will get it fixed. I'd love to use this to teach my kids about how fission works.