Finish the Mass, Volume, Density activity if you did not do so in class.
Include title, purpose (to correctly measure mass and volume of an object, and calculate its density), materials, procedure, data/results (include a table, show formulae, provide sample calculations and be sure to include units at every step),discussion (discuss results, show that you have an understanding of mass, volume and density, discuss problems encountered, make recommendations/suggestions/improvements, etc)