There are some good slides of hornworts and liverworts available. The large flip-page chart has a moss life cycle on it and a marchantia life cycle. Point out that this is the first step towards life on land, and go over things that were needed; how do you spread spores/eggs/sperm when there's not always water to swim thru? If it's been a rainy week, you might be able to find some tree moss with visible sporophytes. There's a big jar of spaghnum moss in the window with some sporophytes, and there's a petri dish with a dried-up bit of moss in it with the hair-like sporophytes visible. Point out the venters with the archegonia, and how all three of the bryophytes (and many of the other lower plants!!!!) have a venter structure. Hornworts do not have the foot/seta/capsule structure of the other two, and their chloroplast(s) are different. It's a good idea to get the students going on a debate over which of the three bryophytes are most closely related; they'll start talking about stomata, physical appearances, etc. The life cycle can be confusing....just point out that it's the same as always. A sporophyte makes spores (sporic meiosis) in ALL the plants....these ALWAYS grow into gametophytes, which produce gametes by mitosis. The gametes ALWAYS undergo syngamy and make a zygote, and a zygote ALWAYS grows into a sporophyte. It's just the names of the parts that produce these structures that change.