Spongebob and School of Rock shouldn't require you to get in line very early before the box office opens. The popularity for both shows (especially SOR) is not so intense that you'd expect a crowd to be there for rush. Most people I know who saw Spongebob got their tickets easily through the digital lottery, morning of the performance. Last report on the Spongebob rush was people were able to show up an hour before the performance and still get rush tickets.
"Mostly, I loved the size of these people's emotions. Nobody has emotions this size anymore. Outsized emotions. Operatic emotions. Kushemski and Vanda are like Tristan and Isolde, they're Paolo and Francesca. Nobody's in total thrall like this anymore. Nobody's overcome by passion like this, or goes through this kind of rage." Thomas, Venus in Fur