Morning test

Please help me correct the paragraph below. Thanks a lot.

Sam always takes the school bus to school. But one day his classmate, Frank, said he would give him a scooter ride. At first, Sam hesitated for a while because he thought riding a scooter was dangerous. However, Frank said he was a great scooter rider and that it would only take five minutes to get to school. Frank insisted on giving him a ride, so Sam took up his offer. However, they got stuck in a traffic jam and couldn’t move. On that day, both Sam and Frank were late for school and missed their morning test.