Mortensen more than Math was designed for students of all ages. Once you become familiar with the blocks yourself then let the students explore, discover, and gain experience with the concepts being presented through play. When working with students think about directed discovery versus rules to be memorized. The concepts are meant to be learned and understood over time not all at once so if something seems too difficult for them, change it up, and come back to it later. Remember math is supposed to be FUN so quit working while they are having fun. Leave them wanting more.