I suddenly remembered this song when I was teaching ukuleles this week. You can sing the whole song to a C7 chord, which must be the easiest ukulele chord to play (a no-fail item in the end-of term showcase?). Strum twice per bar.
You can do actions; train movements with the arms, point down the line, jump on the word JUMP, hold out palm and point to it for “money back”. Yes – thumbs up, No – thumbs down, Maybe – hands, palm down, rotate from side to side to show indecision, So – hands palm up.
Getting the children to all jump at the same time is tricky – they have to bend their knees slightly during “If the train should” so that they can all lift off together on the word “jump”.
I’ve also experimented with changing the words; “We all like to go to school, going to school is very cool”
or topic based “Stone-age life was very tough, Living conditions were rather rough”. You might want to miss out the Yes, No bits. This could be a composition (work it out and write it down beforehand) or improvisation (just go for it) activity.