Engineering challenge project activity for STEM curriculum in grades 4-12. Students will design, build and test a free standing tower structure made using only spaghetti and marshmallows. You will need spaghetti, marshmallows, rulers and a scale to weigh the structures. You will also need an egg to place on the top of the structure. The tower must hold the egg for 30 seconds. The towers are evaluated by the total height. The activity sheets include: Introduction, Equipment List, Procedure, Design, Predictions, Evaluations, Test Results, Conclusions, Teacher Notes and Building Tips. The test results section requires the students to take measurements. The conclusion section includes 5 reflective writing prompts. The students can complete this activity individually or with a partner for a collaborative learning opportunity.