Trams leave every 30 minutes.
We've found that the best time to visit the canyon is in the spring before it gets too hot and before the monsoon season starts. If you pay to take the shuttle to the top of the canyon, you can get off at any of the stops and explore. We like to take the shuttle to the top and then back down to get off at stop 8. There are bathrooms there and a trail that leads off to the right to the rock and water pools. We love to swim and picnic there. Many times we have been the only people there and we can swim and explore for hours. Once the kids are worn out we take the shuttle back down to the visitor's center.
On our trip to Tucson, we took the 45 minute tram tour up Sabino Canyon. It’s a very scenic ride up the canyon with the guide pointing out scenic points and sharing history of the canyon on the way up. The guide is quiet on the way back and let’s you enjoy the view without interruption. People rode with little babies, preschoolers and school age kids. Those with teenagers were more adventurous about getting of the tram and hiking. You can choose to stay on the tram or get off for an easy walk on the tram road. I saw many families with strollers.
Being tourists who hadn’t done our research, we weren’t really aware that we could jump on and off the tram. We just thought it was a tour. We were on the 2nd to the last tram of the day which didn’t leave us with many options for exploring. There are 9 stops on the Sabino Canyon Trail. It seemed like some of the best swimming and hiking areas were stops #6-#8. I’d suggest staying on the tram the whole way up the canyon and decide where to jump off on your way back down (i.e., jump off on stop #8 and hike down to #6). Hang on to your ticket stub and you can ride up/down the road all day on the tram. Once you leave the canyon on tram and go past stop #1 towards the entrance, then you can’t use your ticket to go back up.
Tours are $8 per person and they only take cash. The Visitor Center was also closed when we arrived back at the end of the tour, but I would have liked to see it.