Levitating train...

My husband and older son are in the process of building a levitating train for the second time. The train is being build for the science fair sponsored by the cyber school that my son attends. The first train that they build levitated about as well as a bottle of best prenatal vitamins. Finding the right type of magnets has been quite a process. We must have bought half a dozen types of magnets and have yet to replicate the project as it was shown online. My son has a keen interest in this type of technology and reports that these are going to be the trains of the future. All I want right now is for the one in my dining room to work as it is supposed to. We can worry about saturating the market at a later date.