Take a drive up to Mount Lemmon, going up 9,000 feet in elevation with several pull offs to take pictures, its a great way to get out of the heat and enjoy the outdoors. There is a variety of little shops and places to eat (the cookie cabin is our personal favorite), along with the ski resort. In the summer time you can go up the ski lift and explore or just take in the great views.
Go visit Colossal Cave where you can take a tour in the cave or just sit on the stone covered patio and enjoy the views.
Enjoy walking around the little western town with small gift shops, rides, and restaurants. Stop at Pinnacle Peaks steak house for good food, you won't be disappointed. It's free to walk around the small town.
Drive through the National Park and stop at the visitor center. There is typically a $25.00 vehicle free to enter the park.
Please refer to the pima air & space museum for prices. Explore all different types of aircrafts. Sometimes NASA has their SOFIA aircraft there to tour.
Enjoy the zoo in Tucson! Very reasonably priced and with several animals to see. Please refer to the zoo website for hours of operations, summer hours may vary due to higher temps.