The objects range from naked eye objects such as the Moon, the Plough, and Casseopeia; to objects that can be quite difficult to see without equipment, like a telescope, such as a moon of Saturn (Titan). There is a PDF observing guide that not only lists the objects, but describes how to see the particular objects. The PDF is available here.
If you decide to take part, then you can download the observation record form from the BBC website. Make sure you get your results back to the BBC using the forms on the link by the 24 April, if you would like your results to be included in the May programme.
The Moore Marathon was introduced on the April episode of Sky at Night with this humorous impersonation of Sir Patrick Moore by Jon Culshaw: