Nobody learns logic anymore. That is what everybody says. And they are right. Formal logic has been out of the mainstream curriculum for decades. I believe this is to the detriment of students everywhere. That is why we began our new intermediate mathematics curriculum with formal logic.
The Prodigy Mathematics series is for students who are ready for their first steps into a more abstract and sophisticated approach to mathematics (ages 8-14). It is a bridge between the arithmetic studied in primary school and secondary school mathematics like algebra, geometry, trigonometry, and calculus. The program is designed to be comprehensive, but individual units can also be used as stand-alone supplements to a separate mathematics curriculum.
The first book in the series is "Introduction to Logic." The book starts with the square of opposition of classical Greece and ends with natural deduction proofs of the twentieth century. Proof structure is much easier to grapple with if the subject matter is mundane, like who sits where at a table. The same sense of premise, claim, and justification is employed in formal mathematical proofs. So think of this as a primer for abstract reasoning in mathematics. Get a copy for your little genius today!