Even though it's Mario, don't expect an exciting adventure...
So as Mario, you enter Bowser's Museum in search of Yoshi, who was 'captured' by Bowser upon approaching the building. It's kinda lame, the whole 'sense of mission' and all. As Mario, you collect items from history that the Koopa King stole and return them to their original time. It's not something I recommend for a school substitute, but hey, buy it for collecting reasons if anything. I guess developers wanted to see where Mario's strong points were, so they decided to dump him in an 'educational' video game and 'test' the waters. (no pun intended)
So what the heck. Buy it cheap somewhere and give it a shot on a rainy day. If you don't like it, then save it for fifty years and maybe someone somewhere will pay some serious cash for it. Just a thought.