When I was young we used to take 6 kids in the back of the 3 wheeler and drive all the way to the pub on two wheels, get drunk then dive all the way home upside down.
Jokes aside: I saw a three wheeler (2 at the back and one at the front) do something like that last year. Fortunately none of the kids in the back were seriously hurt. It just finished up on its side, at a slow speed, with a lot of frighted and bruised kids on the ground. By a miracle no-one finished up under it.
Has to be said the one-wheel-at-the-front configuration is less stable.