I run a fieldtrip that requires a fair bit of a walking around a location which is a bit hilly and slippery in places.
In the first few years of running it, I would ensure there was a member of staff at the back for those students who struggle with the physical aspect of the trip. However, students still felt the pressure to keep up. After running the trip, a couple of times, I realised that it would be better to have a lunch break immediately after the most challenging part of the walk and I communicate this to the students. This has enabled students not to feel rushed to keep up and that they can take their own time. The students know that after this difficult bit there is a break coming up and that they will have a chance to sit down. I think this approach makes it a little less obvious that you are accommodating different needs and it makes it less stressful for students overall. It is only through running the trip several times that you realise specific students’ needs for a particular trip and can start planning and factoring that into the day.