It was a long time ago that we went, with dds then in mid/late teens. It was one of the cheaper safari + Mombasa holidays, 3* hotels, not the lux ones, but still brilliant.
I don’t know whether it’d be the same now, but one thing I really wished I’d known beforehand, was to take a stack of cheap biros. So often when we stopped, children would run up clamouring (very nicely and cheerfully!) for pens.
At one point we stopped and bought a whole carton of Bics to dish out!
Dh and I had visited similar places before, but for dds, who’d never seen anything outside relatively affluent countries, it was very salutary for them to see how happy the children were, just to get a pen. IMO it really brought home to them how so much of the world lives.
One dd later went on to work for a major humanitarian charity and subsequently saw much worse poverty/privation than we ever saw in Kenya.