This is what I came up with (and I know some of them aren't very suitable for the end of summer, but let's give it a go!): turnips, pumpkin (butternut and Golden Nugget), climbing beans, bush beans, snow peas, sweet corn, parsnip, beetroot, onions, broccoli, pak choi, cauliflower & peas.
The small people of the family were keen to help, so if these seeds germinate, I will get my wild garden - I encouraged them to move the mulch aside (with gloves on) so the seeds would at least be somewhere in the vicinity of the soil, but then they spotted a spider, and it was seed scattering from then on. We watered them in, so with a bit of luck most of them managed to work their way down through the mulch.
Regardless of how successful a technique it is (and realistically the odds aren't good!), it was fun, Miss Tizz and the X-man enjoyed themselves, and I feel like I've achieved something over the weekend.