Relatives gasped in shock, then sobbed, as Campbell Devlin, 30, was found guilty of the lesser charge of careless driving.
One woman shouted: "These mothers will never sleep again." Other people yelled abuse from the public benches at Glasgow Sheriff Court.
Amid emotional scenes outside, furious relatives complained about theverdict. One man said: "The law has been carried out, hasn't it? I feel as if he has torn my guts out."
John McKenzie, 28, of Gorbals, whose girlfriend lost a 13-year-old relative, said: "It's an outrage. It's not going to bring anyone back, but it's an outrage."
Devlin, of Rannoch Street, Cathcart, left later by another exit. The jury also cleared him of two charges relating to alleged tachograph defects.
Sentence was deferred for social inquiry reports.
The case came after the accident on 18 September in which a double-decker carrying Guides back from a day trip hit a bridge in West Street.
The court heard it was one of two bridges 12 metres apart.
Devlin got safely under the first and higher bridge, but his bus - 13ft 6in high - struck the second, which was 10ft 6in high.
Three Guides aged 10 and 11 and two Guide leaders died. Fifteen other Guides were injured.
The court had been told that Devlin passed his test to drive a bus the previous April and joined the bus company Clydeside 2000 weeks later.
On the day of the crash, he was being given directions to Drumchapel, the Glasgow suburb where the Guides lived, by a Guide leader who told the court that the bus driver was not sure of the way.
Devlin, who broke down in tears several times, told the jury he saw no warning signs and did not brake. "I thought I was all right...I was following the car and I thought it was all right and my mind was on other things."
The Guide Association said it was "relieved" a verdict had been reached for the sake of everyone involved. It added: "The memory of those who were so tragically lost and the strength of those who were injured will continue to inspire the Guiding world and the public at large."
Clydeside 2000 said Devlin would stay suspended from duties "until the company is able to consider his position".Reuse content