Sessions make more sense when they are not just one offs floating in the ether until the next session.
Link your unit to your topic. Make it have purpose and meaning for your children.
Link 'Caring for the environment' in Geography to PSHE through sharing opinions, setting goals, showing likes and dislikes, participating in discussions on the local environment, writing letters to the local council to share concerns etc.
Use 'Dinsosaurs and all that rubbish' as a talking point.
Use Katie Morag and investigating Island homes to explore different communities and recognising that people live in different ways.