Making a fire truck, I realize, is a good way to reinforce shapes, which my little guy is very interested in. You have circles for wheels and the rectangle for the truck and can do a square for the cab.
This construction paper fire truck from No Time for Flashcards, a fellow Kids Co-Op blogger, is one of my favorite fire truck crafts.
Photo from No Time for Flashcards
And, I love this handprint firefighter craft from Tippytoe Crafts.
Photo from Tippytoe Crafts
Another simple idea is to do a big F is for Fire (and covering the F in scraps of orange, yellow and red paper). (This pinboard has lots of other fire safety activities - including a fire safety sensory tub).
Since, I have a firetruck crafts, I thought I would also link to some books about fire safety. Here's a pretty good list. There's also at least 1 or 2 books on the pinboard referenced above.