My experience getting discounts:
1. Kunming bus/subway card
10% discount over paying cash
I got mine at Dongfeng Plaza subway station.
2. Student card from Chinese-language school
My school provides these to students who want one, had to give them a photo and 10 rmb. Probably others schools do similar. Substantial discount at Stone Forest, 80 rmb instead of something like 180 rmb. Also get in to Xishan for half price, 20 instead of 40. But when I tried to use it at Three Pagodas in Dali, the lady yelled at me for being too old trying to get into a national park. Apparently the age limit for students is 25 at a national park, I am visibly older.
3. I like to walk at Kunming's Golden Temple park, get among the trees and flowers and away from car exhaust, downside is lots of people. Normally 30 rmb per visit, however you can get a pass good for one year for 90 rmb. Pay at main entrance, they give you a receipt, walk up the steps quite a ways to administration building, down two floors to the office that handles the pass. Bring visa size photo. When I tried to renew after my first year, I was hassled when I tried to pay (admin office closed, come back in two days, they closed an hour ago, etc. etc.). Finally I went directly to the admin office and complained. They apologized, accepted my money and gave me a new pass. When you use the pass, they punch out a spot on the card, you can enter up to 30 times in one year.
4. World Horti-Expo Park
I like to walk here as well as nearby Golden Temple park. Problem is it costs 100 rmb per visit. But you can get an annual pass good for any number of visits. Cost 300 rmb, but they ran a special during Chinese New Year for 158 rmb, two weeks in February, two weeks in March. Unfortunately, the 158 special ends March 13. Renewal after one year is 138 rmb. Don't need to bring a photo as they take your pic on site and give you a wallet sized card with your mug on it.
5. Gondola ride from World Horti-Expo Park to Golden Temple
40 rmb one way, 60 rmb round trip. No discount, so I seldom ride. The best I could do was pay 60 for the round trip, take a one-way trip one day, and on a later date use the remaining one-way ticket. I asked first before doing this, basically had to get ok from the laoban on hand. This is only possible by showing the annual pass from 4. above.
Now, are there ways to get into parks for free? I once saw some people defeating the fence at Xishan. Serendipity rewards the intrepid and observant explorer, but that's a topic for another time and place and thread...