But that wait-and-see approach to overseeing Chicago's most crowded high school flew out the window almost as soon as Grishaber took over the Norwood Park school at 6530 W. Bryn Mawr Ave.
"I saw things had to change immediately," said Grishaber, who spent Wednesday, his first anniversary at Taft, painting a classroom. "I couldn't wait."
Grishaber suspended high school's decades-long — and much-loathed — dress code before the bell rang on the first day of school.
"It was a no brainer," Grishaber said.
Heather Cherone says Grishaber knows there's much more to do:
The Taft Local School Council dumped the dress code permanently after a group of students made their case against it at a public forum — part of a strategy to make students take responsibility for their academic performance and become part of the school community, Grishaber said.
"There's a good buzz in the halls," Grishaber said. "Next year, we've got to ride that wave."
Part of that buzz was about Grishaber himself, and the series of humorous videos encouraged students to get to class on time in the morning, including one where he pretended to do BMX bike tricks.
The videos helped students feel connected to the administration, which helped teachers get a jump on issues percolating under the surface, Grishaber said, adding another video is in the works.
Taft remains the most crowded high school in Chicago, ending the year with 3,043 students studying in a building designed for 2,184 pupils.
While the hallways were full during passing periods, the overcrowding is manageable, Grishaber said.
Local School Council Chairwoman Lisa Schwieger said Grishaber during his first year "was faced with many challenges and he showed our community that he will not be intimidated."
Schwieger, whose oldest daughter graduated from Taft this year, said the school had significantly changed for the better during her four years as an Eagle.
"I have complete confidence that Mr. Grishaber will have a long, successful career at Taft," Schwieger said. "He desires to not only improve test scores, but attitudes, the culture and working and learning environment as well."
Another of Grishaber's first acts was to give up his prime parking spot, instead reserving it for the teachers of the month.
"I've heard that I have exhaustingly high standards," Grishaber said. "My response is that I don't understand why anyone would want it any other way."
The changes at Taft have paid off, said Grishaber, who often tweets from school events.
"I can't take all of the credit," Grishaber said. "The staff is great. Taft teachers get down and dirty. They have to roll up their sleeves."
The attendance rate rose 2½ percent, and the number of freshmen on track to graduate rose 3 percent during the 2014-15 school year as compared with 2013-14, Grishaber said.
The number of clubs at Taft rose from 64 to more than 110 this year in an effort to get more students involved — and motivate them to come to class, Grishaber said.
In addition, Taft students' average score on the ACT, the most widely accepted college entrance exam, rose from 18.5 to 19.6, Grishaber said. Next year, the goal is to hit 20, and eventually surpass the 20.2 state average.
Another sign of progress is the decision of more seventh- and eighth-grade students from Taft's academic center to go to high school at Taft, rather than a selective-enrollment high school, Grishaber said.
Taft also became the hardest International Baccalaureate high school to get into in Chicago, Grishaber said.
But leading Taft through so many changes has been difficult, Grishaber said, adding that he is in charge of everything from the push to build a multi-million dollar artificial turf football field to making sure the bathrooms have enough toilet paper.
The all-consuming nature of the job led to many sleepless nights, Grishaber said, adding that he would often fall asleep worrying about issues, dream about concerns and wake up to start the cycle all over again.
"It definitely took a mental toll," Grishaber said.
But the ceremony for Taft's more than 600-student graduating class made it all worthwhile, Grishaber said.
"I got to shake the hand of students who I know needed a great deal of intervention to get their diplomas," Grishaber said. "That was the best thing ever."
But Grishaber said more challenges loom on the horizon, and he has more changes in store.
"I'm worried about the budget," Grishaber said, a day after Chicago Public Schools officials announced they would lay off 1,400 employees in an effort to save $200 million and bridge a massive budget deficit. "It makes it really hard to hire people."
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