Planning a field trip may feel a bit daunting if  you've never done it before, but there are "tricks" to help you make it a smooth and satisfying experience for everyone involved.

Choose a field trip activity or venue. You can find many field trip suggestions under the Field Trip Ideas section of this site. Choose one that fits the interests and inclinations of  your own family - make it relevant to your kids and you increase the likelihood of it being a successful outing!

Contact the venue and get the info you need to share with others (location, date, time, cost, method of payment, min/max numbers of participants, appropriate age grouping, amount of structure, policies and rules, parent participation, younger siblings). Let the program coordinator know that this is a homeschooling group and that most parents like to accompany their kids. Some locations are used to working with school groups so their adult-to-child ratio tends to reflect that. However, they will often bend their policies for homeschooling families as they'd like kids to sit quietly through performances/activities and having more parents around tends to help. Please be aware that there may be additional costs for extra adults in the group, and it's good to know that at the time of booking.

Post it on a local list, such as VicHomeLearn, to find out who would like to join you. Be clear about the details, especially with respect to most appropriate ages and the amount of structure involved. You may also want to set a limit as to the size of the group, as an intentionally small group means that kids get more attention from the instructor or docent. It also tends to be much easier to facilitate trips for a smaller group.

Simultaneously confirm the field trip AND take people's money. This can be the most difficult part of planning  a field trip. As trip organizer, you are ultimately responsible for covering the costs of the activity when applicable, and there are a few horror stories of organizers left holding the bill. If you have to collect money in order to pay for the trip, do get the money upfront. There are some kind souls who don't do this and that sometimes means they pay no-shows out of their own pockets. It may take some forethought to do this, but it is possible to set up a PayPal account for field trips (with the funds directed to your bank account) and people can confirm their spot in the trip immediately. If people don't want to use PayPal, then they can send cash by mail (prior to a deadline that you set) to hold their spots.
 
There will always be cancellations. If people back out before payment and that affects you financially, try to find  others to fill their places. If they've already paid, then it's up to them to find someone to take their spots (and reimburse them directly). This is much simpler for you! If you've planned a highly desirable field trip that fills up, be sure to have a short waiting list so you can slide folks into spots that unexpectedly empty. 

Remind people. Remind them a week ahead. Remind them the day before. Remind them the day of, if you really want to. It can be as simple as saying, "so looking forward to seeing everyone at 1PM at the blah blah blah". Most people really appreciate reminders. You can use a list to do this, but be sure to also be clear that the field trip is full (so you aren't contacted by disappointed people who were hoping to join in at the last minute).

Give people some wiggle room in terms of time. You may need to give the start time as being 10 minutes or so earlier just so people have time to find parking, etc. A matinee downtown on a weekday is a bit of a nightmare as the meter parking is only 90 minutes, so people will need to find a lot or a parking garage... and then they may need to walk to the venue. So, let them know to give themselves an extra 15 minutes prior to the suggested arrival time  to sort that out. 

Distributing tickets. If there is assigned seating and you have tickets, you may want to factor the cost of a stamp into the cost of the tickets and mail them out ahead of time. That can come back to bite you if someone loses their tickets (or gives you the wrong mailing address) as you'll need to meet them at the box office to put it to right, but it might be less hassle than trying to hand them out on the day or trying to meet a large group on a street corner and waiting for people who are late (because there will always be people who are late and you don't want to miss things because you are the one waiting for them - it may be possible to ask the box office to hold the tickets for them). If you send out tickets ahead, do keep track of who has which seats (especially in the event that tickets are lost).

Have fun! We organize field trips so that we can broaden our children's worlds and that should be an enjoyable experience for the whole family, including the adults. Hopefully, these suggestions will help make your event a great time for everyone!