For the homework assignment on the Aug. 14th episode of 'The Glee Project,' the final four singers had to belt out 'Lean on Me,' a simple song that is driven by the voices that sing it. Guest mentor was the spectacular Kevin McHale, who plays Artie on 'Glee.'

McHale had the task of deciding who sang 'Lean on Me' best and to get the point of "generosity," which was this episode's theme, across. McHale told the remaining hopefuls that the show is truly like a family. He said that he and his castmates are each other's support system, which is critical when you deal with tough times and long days. You have to be able to lean on each other.

McHale said that Samuel was a bit disconnected when he sang but that he blossomed during the ensemble portion, while he felt every single word and note that came out when Alex opened his mouth. He said that Lindsay was completely into her performance and that Damian was connecting with everyone. McHale was uber diplomatic with his "I wish it could be a four-way tie" comment, but he eventually selected Lindsay as the winner of this particular homework assignment. Post-win, she was cheerful that she "finally did something right."

McHale let Samuel, Alex, Lindsay and Damian know that they'd be playing instruments in the video for this week's song, which was My Chemical Romance's 'Sing.' McHale made them feel at ease by admitting that while Artie plays instruments, he does not, so he has to fake it, which is also known as acting.

In his one-on-one mentoring session with Lindsay, which was her reward for winning the homework assignment, McHale showed her how to hold the instrument, so she could be believable. It was the type of hands-on mentoring that could help Lindsay seal this thing.

The season finale of 'The Glee Project' airs next Sunday, Aug. 21.

Watch 'The Glee Project' Contestants Perform 'Lean on Me' on the 'Generosity' Episode