Science - Which animal families are invertebrates?In this lesson, we are going to be learning about 3 different families of animals which are invertebrates. Invertebrates are animals which do not have a backbone. They either have a soft body, like worms and jellyfish, or they have a hard outer casing covering their body, like spiders and crabs. We will be learning specifically about crustaceans, arachnids and insects which are types of invertebrates. You will need a pencil, a piece of paper and most importantly your brain!