That looks interesting and you can do it in one lesson. Will definitely try this one, thank you!we did there other one where you put the cotyledons on blue tak in a film tub and they bend.
View attachment 4384
An intriguing way to demonstrate gravitropism in action over the course of a lesson, using the hypocotyls (stalks) of small seedlings. Students may be surprised to see how quickly the seedlings respond to gravity.www.saps.org.uk