Prior to break, the 7th graders had the chance to play with an awesome Mars simulation that was put together by NASA and JPL. This was a perfect end to first and second quarter since we studied both astronomy and geology. This unit can be extended for multiple days depending on how much background information that you want to build. Since we had already spent a great deal of time back in 1st quarter learning and analyzing the missions of the Mars rovers, my students just spent 2 days planning missions and executing them. This is an excellent STEM activity since students must budget their money, calculate their load's mass, and play a balancing act between what is required and what is wanted. My husband picked up their newest version when he went to JPL to see the curiosity launch. An older and similar version is here. I printed the mats and cards in color and laminated them so that they can be used multiple years. This was such a perfect activity for my gifted kiddos since they love activities just like this!