Teachers, please help!

[LaBelleDameSansPatience]

On Monday I have an observed maths lesson. It must be Using and Applying/problem solving for a mixed age class of y5/6, ranging in ability from Level 2A to 5B. (My maths ability is probably about 4B!) Our topic this term is Ancient Greece or, of course, Easter.
I have no idea what to do or how to structure it.
Any ideas?

Oh and yes its really difficult without a TA. Even if your TA isnt doing groups you need someone around to tackle any problems in the independent groups. The only thing I think you can do is have a bank of activites that you know the children can do (tables practice for example) if they are finding their independent work too hard.

It doesnt fit all classes (no matter what our Head says), you just have to find a way to make it work. I know some schools have gone back to the pre-national curriculum style of having, for example, 1 group doing their art, 1 on a comprehension exercise, 1 doing an input with the teacher and 1 on the computers.

That's really interesting Wellthen - thanks! Always good to hear of new ideas :-)