Brian Burleigh found Britannica School:

• Moderately reduces teacher workload“If a topic can be researched thoroughly by a student without the need for teacher intervention, the Britannica website is an excellent resource.”
• Slightly improves teacher knowledge“Personally I don't use it for personal knowledge but I know that I could.”
• Moderately improves attainment
• Significantly builds student knowledge“Students can easily check sources and learn critical-thinking skills which directly impact the uptake of knowledge.”