Cross Keys Foundation will partner with Big Thinkers Science Exploration to sponsor science assemblies at each of the five elementary schools in the Cross Keys High School attendance area of DeKalb County. The first event was scheduled for Wednesday at Woodward Elementary, where about 300 fourth and fifth graders will take part in 50 minutes of science demonstrations and presentations. Assemblies will also be scheduled for Dresden, Montclair, Cary Reynolds and Oakcliff over the next year.