I have always kept Jade Plants in my Leopard Gecko enclosures without any issues. I don't think they are poisonous either. They are a tough plant that doesn't have any sort of thorns or sharp edges.
That I'm not so sure about that. My leopard geckos weight a lot less then a beardie and they don't climb that much. But there are several different types of Jade Plants. Some species are tree or bush like while others are ground covers. Mine are the bush-like variety. The only thing you have to watch with these plants is that you can't really let their soil get too dry.