My recommendation is to skip Manly Beach (which I didn’t find attractive although easy to reach on a 30 minute ferry) and head directly to Bondi (you’ll need a bus or combination bus/subway to get there). I opted for hiking a five beach coastal path (after shopping of course) from Bondi to Coogee.
The guidebooks said the walk was 6km and would take two hours. I’m not sure if the writers actually went on the hike or not. I’m in good shape and it took 4-5 hours to cover what I believe to be 10+km in distance.
The walk takes you up and down staircases, and along the coast the entire distance. I carried my shopping bag with a plaster fish (from a Bondi thrift shop) thinking it was a short hike. I was glad to reach Coogee Beach and finally get a swim. The water was bracing in late November but felt great to cool down after the hike.
Of the next three beaches, Tamarama, Bronte and Clovelly, I liked Bronte the best. It was popular and had a nice park area for families. Clovelly, however, had a sheltered swimming area that might work well with children.
After reaching Coogee Beach and having a swim, I hopped on the bus for a 45 minute ride back to Circular Quay. The plaster fish by the way made the journey in one piece.
As a native from Sydney I’m disappointed that you didn’t explore more of the northern beaches, such as Whale Beach and Palm Beach. While Bondi is great, sorry to say it is a bit of a tourist trap!
I lived in Sydney for a semester at UNSW. Bronte was definately the hidden gem of a beach. Nice cafes, family friendly, and a beautiful pool.