Emilie Sibbesson of Canterbury Christ Church University has written a guide to the Stone Age with lots of factsheets, twelve lesson plans, supporting resources and loads of beautiful illustrations that is free for teachers to download and use. The information in there is not exclusive to Kent, though the suggested places to visit are all in Kent.
You need to create an account with them to download it, but it is free. Go to their website to get hold of this great resource.
There are great ideas like using toilet roll (though it has to be 1000 sheet!) for a timeline, challenging children to try to move balls across a room on all fours, guidelines for cooking fish wrapped in nettle and dandelion leaves and clay, and some great drama to undertake at the end of the block. The resource has been piloted with several Kent schools and so the activities have all been well tested.
The illustrations by Penny Bernard are also fantastic and give a sense of the richness of culture in this remote time.