IXL Math Powers over 150 Percent Growth on MAP Benchmark Assessment

A case study of Saint Lucas Lutheran School in Milwaukee, Wisconsin

Saint Lucas Lutheran School is a private K–8 school with a highly diverse student population that includes many families living in poverty as well as more traditional private school families. When Chris Luebke joined the staff in the fall of 2016, his middle school math students were all over the board in their mastery of grade level math skills. He brought in IXL Math to supplement his core curriculum and provide his students with individualized math instruction.

Teaching to Both Ends of the Bell Curve

When Chris looked at the testing data for his new 2016–2017 classes, he realized he had a challenge on his hands. “They were all over the map,” he says. “About one third were significantly below grade level, a group of them were working above grade level, and the rest were somewhere in the middle.” He knew that it would be difficult to design lessons that would meet the needs of all students with such a wide range in existing skill sets.

Without a differentiation strategy, Chris recognized that his standard math curriculum would both fail to push his academically advanced students and go over the heads of students who were already lagging. “It’s easy to just teach to the middle. It’s the most efficient use of time,” he explains. “But when you don’t meet the needs of students on ends of the bell curve, they won’t see any academic growth. I want every student in my classroom to grow.”

“When students see the progress they are making, they get really excited. It’s very powerful to have a program that gives each student exactly what they need to grow.”

Chris Luebke, middle school math teacher

An Individualized Approach to Math Instruction

With IXL, Chris was able to provide tailored instruction for every student in every class. The school uses the MAP benchmark assessment from NWEA to monitor student progress towards grade level standards and identify areas of need. Chris used the NWEA data to determine where he wanted each student to start on IXL. He says, “It’s not enough to know a student is below grade level. You have to know what specific skills they need to work on. One student might need fractions, another might need statistics or charts and graphs.” Because IXL is already correlated to their standards, Chris was able to easily pinpoint the specific IXL skills he wanted each student to tackle.

During their individual practice sessions on IXL, students can work at their own pace on the skills they need the most, whether that means working ahead or going back to practice skills they may have missed. Chris says this targeted instruction and practice has been invaluable for students who have struggled with math in prior grades. “It’s like filling potholes in a road,” he says. “It’s been really eye opening for students when they can see where the disconnect has happened and go back and correct it. Sometimes, it’s just one or two skills they missed in third grade that are holding them back.”

“No matter what curriculum you use, IXL is a great tool to use—in my estimation, the best one you can use, especially when it comes to individualization.”

Chris Luebke

Accelerating Growth for All Students

Chris says his students responded positively to the program from the beginning. “They love it because it is useful and purposeful,” he explains. “We had another program that was more gamified, but most of my students actually prefer this. It doesn’t waste their time.” Students appreciate the immediate feedback and are highly motivated by seeing improvements in their SmartScore. All that targeted instruction has really paid off. On average, Chris’s students grew 150 percent on the MAP benchmarks over the last school year, representing a year and a half of growth. He was especially pleased to see that both accelerated students and those who had started the year from behind made strong gains.

But there is more to the story: student growth rates were directly tied to the time they spent on IXL and the number of skills mastered. Students in the top quartile of IXL usage grew an amazing 274 percent—almost three full years of growth in a single school year!

(based on IXL Usage)
Average Number of
IXL Skills Mastered
Average Growth on
1st 159 274%
2nd 152 188%
3rd 113 137%
4th 102 60%


“I tell my students that it’s hard work that makes the difference, and I demonstrate that with the data,” Chris says. “No matter where they are starting from, I want all of my students to understand that working harder really does lead to more progress.” Especially when all that hard work is happening on IXL.

A copy of the full case study is available for download here.