Been going to this park since I was little and the water play ground is still the same. Best fun for the kids if you don't mind them getting wet!
There the train ride which is fun but could do with a make over as this too hasn't changed since I was young and is a bit run down.
Heaps of open space for kids to run around and kick a ball.
If your in Canberra and looking for a great BBQ or picnic spot, Weston park is it!!

Based on summary on official Canberra tourism website & recent trip advisor reviews decided to ride bikes from Questacon to Weston Park, with 4 & 7 year olds on training wheels. The prospect of a real maze & treehouse by Lake Burley Griffin was enough to provide the incentive needed for them to pedal the 5kms. Luckily my kids were easily appeased with lollies as a treat for their fantastic efforts! No maze/ or treehouse. Extremely tired miniature railway & dingy cafe. The park itself was fine, it amused the kids - a few climbing spiderweb frames, swings, diggers in sand pit & water play area. My beef was with the official descripton of the park which is extremely misleading!!!

The water play features are great. Musical bridge is also fun. Great location with views. Great BBQ and fishing spot also.
Have a swim or bring a kyak.
The mini train sux but little kids still like it.
Even go for a walk and see many Kangeroos laying around.

What a great place to go for a picnic with playgounds for the kids, a safe swimming area and it is a peninsula so there is plenty of water to watch the water birds and the sailors. There is plenty of room for the kids to play and thousands of shady trees - so beautiful in Autumn. There are two plant nurseries near the entrance as well. The whole area is free to go in - just bring your food and a frisbee!