Two years ago we spent Feb. Vacation in Aruba. We went on a Jeep Tour. Very, Very Bumpy. No seat belts. Jeeps in very poor condition. One broke down, another had a flat. Between the remaining 3 jeeps we were able to find enough pieces to get the jack to work. Thank God my husband was a mechanic, as even the tour guide had no experience. We ended up late for the designated snack place, which isn't a big deal, except that in our party was my 11 year old diabetic niece. Who, then became low....The snack turned out to be watermelon (much different then we were told it would be) but that was because we were running so late. Tour ended at Baby Beach for lunch (awful - of course it had sat out for 2 extra hours - chicken now room temperature, potato salad, room temp. we figured it wasn't safe to eat). The snorkling at Baby Beach was great. Warm water, lots of colorful fish.
For children that age I would not suggest a Jeep Tour, maybe the Safari Tour which went to almost all the same places, yet in a different type vehicle, much safer looking, and cleaner. The Butterfly Farm is a nice place for children and any of the beaches Palm or Eagle - lots to do there. Tubing, Banana Boats, Parasailing...
Aruba is beautiful. Have fun.