The Tidbinbilla Nature Reserve is just outside canberra, giving you a chance to have a BBQ, let the kids play at the discovery play area, or try and catch a glimpse of a platypus in the sanctuary. If you are a local, I recommend getting an annual pass, as the value in a year is pretty good.

Costs are as follows:
Annual Pass private vehicle (up to 8 seats)$30.00
Annual Pass private vehicle (concession) $20.00
Annual Pass motorcycles and pushbike $15.00
Annual Pass motorcycles and pushbike(concession) $10.00

you can also pay for the day, the day passes would be very expensive if there were lots of outings there.

Day Pass private vehicle (up to 8 seats)$10.00
Day Pass private vehicle (concession) $6.50
Day Pass motorcycles, pushbike & pedestrians $5.00
Day Pass group entry (coaches, per passenger) $2.00
Day Pass group entry (school groups, per passenger) $1.00

I have attended a child's birthday party there in summer and have taken the kids out every weekend all year round on days that were sunny. It gets them away from normal play areas and there are things to see and do all over the rerserve.

In the sanctuary, there is a viewing platform where the cunninghams skinks come to bask in the sun. they are tolerant of kids and don't disappear when there is noise around. My sons absolutely love taking photos of them.

The reserve has volunteer guides as well, these people are very happy to talk about the local flora and fauna, and they really get the kids to engage and understand the local canberra area's nature.

worth the visit.

The Visitor Centre is open in winter from 9.00am AEST and closes at 4.30PM AEST. In summer it is open on weekdays between 9.00am AEDT and closes at 5.00PM AEDT.

Summer: Week days - Opens 9.00 am (AEDT) Closes 5.00 pm (AEDT) Weekends, public holidays and school holidays - open 8.30 am (AEDT only) closes 5.00 pm (AEDT only)

Reserve Gates: Opens 7.30 am; closes 8:00 pm in summer (AEDT) and 6:00 pm in winter (AEST).

Tidbinbilla is closed on Christmas Day, and may also be closed on days of total fire ban, high winds or for management requirements.

a google search gives you the website and other features at the reserve.