Chicago startups with kid-focused services are rolling out deals for the planned one-day teacher strike Friday, seeking to fill a gap for parents and to draw new customers.

They're offering everything from easy-to-book babysitters to parent-child classes to full-day camps - complete with strike-themed discount codes - for the one-day Chicago Public Schools teachers walkout.

"It's definitely a need right now for families, but it's also a fun opportunity for kids to experience something new," said Elaine Russell, chief marketing officer of Dabble, an online marketplace for classes. She also...