Once your groups are made and rooming assignments are taken care of, you'll need to do a few more things before you have your pre-departure meeting. Here are a few things to consider:
Travel to/from airport: You'll need to decide whether it is each man for themselves, carpooling or arranging for a charter bus. There are pros and cons to each.
Each man for himself: This way is probably the cheapest for your travelers, depending on how far you are from the airport. This also allows parents who are not traveling with their children to extend their goodbyes a little longer. The downside to this is that someone can be stuck in traffic, get lost or just run late which could cause you to worry as the group leader. Also, it's not the most eco-friendly way to travel.
Carpooling: This way is more eco-friendly and can be less expensive than a coach bus or even individual travel. In order for this idea to work, you have to make sure that each car has enough space for the people/luggage. Here again, though, people can be late, stuck in traffic or get lost.
Coach bus (charter): This is my personal preference because while it may not be the cheapest route for your group (depending on size), it is eco-friendly and it ensures that your group will arrive at the same time and check in together. There is no waiting around for any latecomers. Parents will have to say goodbye at the school which might be difficult for some of the more clingy parents but they can always use FaceTime from airport before departure. This involves more work on your part because you'll have to research companies and then collect money for the bus from participants. Another upside is that you will have the bus time to review some important information with your travelers. At this time, I usually assign a number to each participant so that when we come back together as a large group after free time, I don't have to walk around doing a head count. We just count off as loud as we can! I use this bus time to practice!
Here again, you'll need to make a decision. You can have each participant be in charge of tipping their guides, tour directors and bus drivers or you can collect in advance. My recommendation is to do the latter. It is much easier for you and more efficient than collecting on tour. It also gives the travelers one less thing to worry about. I usually go with the recommendation of the tour company on how to tip.
Email or send a letter to your group
Once you have made your decision regarding the travel to/from the airport and the tips, you are ready to draft an email or letter to your group. In the letter, you should let them know when you'll hold your pre-departure meeting and what they should bring with them to the meeting. If you travel with EF, they usually send you a backpack and luggage tag for each participant, which I like to give out at this meeting. For an idea of how to draft your letter, click here.
You're ready to have your meeting! Good luck!