Option 1: More concise and direct
* The studies are designed to make students think.
Option 2: Emphasizing the purpose
* The studies are designed with the goal of stimulating students' thinking.
Option 3: More specific about the type of thinking
* The studies are designed to encourage students to think critically/creatively/analytically.
Option 4: Using a different verb
* The studies are designed to engage students intellectually.
The best correction depends on the specific context and the desired emphasis.