This has been asked many times before but..

[butterfly]

..if I care for a child one occasion a week for 2.5 hours should I have a learning journey for him?

[kellyskidz!]

If he's in nursery or attends another setting on a more full time basis than with you, then no, I don't. I'd do a learning 'scrapbook' with a few photos a month, some observations, some artwork they've done and leave it at that xx

[Rick]

..if I care for a child one occasion a week for 2.5 hours should I have a learning journey for him?

I think I would combine a diary and obs book. You wouldn't do many obs but I don't think you can do nothing

[Mouse]

A LJ is never compulsory, what you have to do is show progress & development. The amount you do is relative the the time you have the child. It's up to you how you show it.

I have one mindee for 2 hours a week. I email his parents after he's been here with a round up of what he's done during those 2 hours. He started as a baby, so very often slept for the whole 2 hours! Once he was moving around I'd write about how he was trying to crawl, could sit himself up etc. If parents mentioned he'd done something at home, I'd saying "following on from you saying he's liked singing nursery rhymes at home, we've had a lovely music session, playing instruments and singing Wheels on the Bus".
Every now & again I'll include a photo and comment on what he's doing, what it shows. I often used the photos to show the characteristics of learning (eg. if a photo shows him really concentrating on something.

It doesn't take more than 10 minutes to do & I have all the emails saved in a folder on my laptop. They show his progress from when he started, how I plan for him and I work with what parents tell me. I feel that's enough.

[butterfly]

This child will be in school full time so I will be collecting him, driving him to mine, giving him snack, he'll chill out (and probably watch TV) and then have tea.

[kellyskidz!]

This child will be in school full time so I will be collecting him, driving him to mine, giving him snack, he'll chill out (and probably watch TV) and then have tea.

No then, because school are his primary carers and will be doing eyfs development with him, if he's under 6 or key stage if he's in y1 or older.
When OFSTED came I didn't have a LJ for my pre schooler because he was at morning only nursery more often that with me, but I showed her that I'd found out what topics they were covering and had followed it up when he was with me, even though it was more basic that id normally do for my full timers
You can support what he does at school with a simple file/scrapbook/journal if you choose, but it doesn't have to be too detailed as he's getting all of that from school xx

[Mouse]

This child will be in school full time so I will be collecting him, driving him to mine, giving him snack, he'll chill out (and probably watch TV) and then have tea.

In that case, no. My lo who comes for 2 hours is a pre-schooler.

When I had after school EYs children I did them a scrap book with the odd photo in it. One of them liked building really intricate things with the building blocks, so I'd take a photo of whatever he'd built. Other times I'd take a picture of them doing a craft etc.