There are loads of ‘treasure hunt’ published trails in London where you can print off the clues. We’ve done a few……good way of learning a bit of history (and trying several new pubs)
Use your travelcards to get cheap tickets to go on the Thames Clipper, kids will love being on the river https://www.thamesclippers.com/plan-your-journey/timetable
The Royal Parks are great - St James’s, Green Park, Hyde Park
Street Entertainers usually in Covent Garden
Mudchute Farm (loads...