They should check plants and record observations on a daily basis over that time period. Each student should create a data sheet for daily recording of data. Number of leaves present Length of selected leaves since some plants have more of a bushy shape Plant height 3. At the end of the four weeks of observation, have students separate the leaves from the roots. It is best to set the leaves aside and allow them to dry before weighing.
Dry mass is the best indicator of plant growth success.
Have the students analyze and graph results to determine which hydroponic system is the best for lettuce. The instructor can have the students share their results with each other by having them present the results to the class. More Activity Ideas Have the students design an optimal hydroponic system based on the results they have collected from this activity.