2 Weeks in Denmark/Sweden-Next July (Itinerary Help)

We found Scandinavia to be deadly expensive on the ground. Went into Copenhagen for a few days before catching a cruise to Warnemunde, Tallin, St. Petersburg, Stockholm and back to Copenhagen. We loved all the cities, but are more comfortable in Copenhagen. The cruise was very reasonably priced and it sure beat $30 burgers at TGI Friday's. We flew over to Oslo and took the Norway in a Nutshell train/ferry trip to Bergen.

My main take away from Davids post is don't eat at TGI Fridays. It's quite possible to eat without breaking the bank if you avoid the obvious tourist traps, go a bit off the beaten track and self cater from time to time. In Sweden you can always find decently priced lunch menus.
I also seriously doubt that a cruise is a cheap option and a downright silly suggestion for travelling between Stockholm and Copenhagen with a 5 year old. The Swedish Railways www.sj.se have some great deals, especially if you book in advance.

A good option for a stop in Sweden with a 5 year old could be Vimmerby and Astrid Lindgrens world. Kalmar could also be nice, but getting there involves a bus or two.
From Copenhagen the usual day trips are Roskilde with its Cathedral and Viking Ship Museum, the latter is great for kids. Another option is Helsingør, with Kronborg Castle (famous from Hamlet), a pretty old town and an award winning Maritime Museum https://mfs.dk/en/. Kronborg Castle is from the same historical period as Kalmar Castle, so one could substitute the other. Another option is Frederiksborg Castle in Hillerød. It's more grand than Kronborg and probably less interesting for kids. All day trips can be easily done by train from Copenhagen, you can search for time tables and everything to do with public transport in Denmark on www.rejseplanen.dk

Well if we talk about Copenhagen you've got a lot for kids in and around the town. I would suggets visiting the worlds oldest Tivoli called Dyrehavsbakken just half an hour with S-train from copenhagen central station. You take either oresundstog to helsingor, S-tog C or regionaltog 1371 and jump off by klambenborg/dyrehavsbakken. I show you some pictures on http://bikedenmark.nu/strandvejen/dyrehavsbakken.html and https://world-info.se/europe/northern-europe/scandinavia/denmark/uncategorized/visit-dyrehavsbakken-during-summer/
In copenhagen you also got an exciting alley called stroeget that leads you from centralstation to nyhavn. from Nyhavn you could try the harbour ferry for an exciting discovery from north to south harbour. Then a trip to Christianshavn where you are able to jump off the ferry could also be an option. And when you go for Kronenburg castle in Helsingor why not a quick trip to Sweden with the small ferry for bikes. You'll see it a couple of hundred meters north from the ordinary car ferry. I wish you a nice trip.

I'll reiterate what Morten said:

A good option for a stop in Sweden with a 5 year old could be Vimmerby and Astrid Lindgrens world.

The pre-trip work is to read all the books before you go. I also don't find Sweden particularly expensive, but I travel relatively low to the ground. Also, yes, there are some lovely towns within an hour of Stockholm...and islands. But there are also many kid friendly locations right in Stockholm. I'd suggest a week in each city and really get to know them and their environs.

There are direct trains between Stockholm and Copehagen that can be very cheap if booked in advance so there is really no reason to stay somewhere else, but of course you can do that if you want to see something else.

Malmö is not worth an overnight stop, it is not that interesting. If you want to see some towns in Skåne I'd suggest Lund, Helsingborg or Ystad, much nicer town. And all easy to do as day trips from Copenhagen.

If you want to stay somewhere inbetween my recommendation is without a doubt Visby, probably the best preserved medieval town in the Nordics. It will be a bit of a detour but it's worth in, and on the way from Visby to Copenhagen you can make a stop in Kalmar, which is nice, but gets far more attention than it deserves on this site.

I am thinking that you likely have your plans made by now. If I was doing this trip I would spend a full week in Stockholm. Stockholm is my favorite city (over Dublin, Rome, Venice, Florence). There are plenty of things to do with a young child, spend a lot of time outside. I would not spend a week only in Copenhagen but there are plenty of places nearby. Roskilde is worth a trip. Also, I loved Ystad. It is beautiful medieval town on the coast. I spent 2 1/2 days there.

Please come back and let us know what you decided.