The tone is neutral with no strong opinions either way.
To express that the event will continue until a specific time in the future the sentence would be rewritten in future perfect progressive tense. Future perfect progressive tense refers to the state of action that will be continuing until a specific time in a future.
Future perfect progressive tense is formed as subject + will+ been + present participle of the verb.
Therefore, the sentence would be rewritten as,
The students will have been painting for an hour without a break to create their Rockwell-inspired art.
Business communication is information sharing between people within and outside an organization that is performed for the commercial benefit of the organization. It can also be defined as relaying of information within a business by its people