The logistic problems of getting an elephant across a river are enormous. The best way appears to be building a sort of pier, the outermost part of it is really a detachable raft. You then tempt the elephant on to to pier with juicy vegetables etc, and when it is in position on the pier end, detach the raft and float your elephant gently across the river. This worked for Julius Caesar.

Roman schoolchildren would greet their teacher with a kiss - yuk!