Hello ladies. I am planning my first field trip with my dck. I mean I always take them to the park but this time I'm going to the children's museum. Since I have never done this, I have a few questions but was also looking for some tips.

I have two 19 month olds, two 3 year olds, and one (my son) 2.5 year old. My husband would be coming along with us so there would be 2 adults. Do you think the 19 month old are too young for field trips? I didn't think anything of it until I started googling. I think they would enjoy it. I would take my double stroller for them for when they need it. I was really hoping to take all of the kids but now I am not sure if it is ok. Clearly one of the kid's parent is ok with it as she offered to drop off and pick up her son and 1 other child in her car. I'm pretty sure the other parents would be ok as well.

Here is what the schedule is looking like.
9:15 - drive there
9:30 - arrival, washroom break
9:45 - explore the exhibits/play
11:15 - washroom
11:30 - lunch
12:15 - leave
12:30 nap at daycare
Do you think 1.5 hours is too much playing/walk around time?

The entrance fee is $8 plus HST for the toddlers and $2.50 plus HST. Do you get parents to pay for the fee? I would of course be buying lunch just like any other day.

Do you guys get them to sign a permission form? If yes, what should the form say? I always take them to the park so they do leave the daycare premises quite often.
However, I've never gone this far before.

If you have any other usefull tips that I may have forgotten, please share as this is my first field trip with this many kids.

I would greatly appreciate some advice and hear about your experiences with field trips.

TIA