SPRINFIELD, Ill. (AP) — Less than quarter of Illinois children were fully prepared to enter kindergarten last year, a new study by the Illinois Board of Education has found.

The study of about 106,000 students was based on evaluations teachers conducted during 2017 of their kindergarten students. The students were studied for the first 40 days of school for social and emotional development, reading and language skills and math skills.

About 42 percent of students weren't prepared in any development area, according to data from the Kindergarten Individual Development Survey, or KIDS, survey.

Seventeen percent were prepared in one area, 18 percent were ready in two areas and 24 percent were prepared in all three areas.

Tricia Burke, principal of Ball Elementary School in Ball-Chatham School District 5, said more data and time is needed to draw conclusions from findings. In her district, 43 percent of students were ready in all categories.

But state Board of Education spokeswoman Jackie Matthews said the data show that more money must be invested in high-quality early childhood education.

"There's actually research showing that children that have high levels of readiness when they start kindergarten are more likely to graduate," she said. "They're even more likely to earn more as adults."

Students from low-income households were less likely to be ready for school, Matthews said. She said those students may have had access to early childhood education programs, but that those programs may not have been of high enough quality.

"What the data shows us is that, statewide, we need to increase our investments in early learners," she said.