7-Segment LED Clock - K8089

I bought this as a mini project to explore building a more complex circuit with some children. Without buying an 12v AC power supply, is there a way to power it using a DC supply?

You can download the manual from this link.
https://www.vellemanusa.com/downloads/0/illustrated/illustrated_assembly_manual_k8089_rev3.pdf
On page 10 they talk about using DC however the clock may run fast or slow.
With AC it uses the 50Hz or 60Hz for the timing pulse.
If you are in the USA or some place that uses 60Hz and use an AC adapter plug the AC adapter in before installing the back up battery. This will ensure it is setup for 60Hz other wise it will default to 50Hz

I am looking how to connect it up to a DC supply and where/how to make that connection.

Thanks.

You can connect it to here polarity does not matter.
See my earlier warning.