Any recommendations for helping a child who seems to forget things all the time?

Today was the third time since school started that Cate forgot her lunchbox. The first time, I kindly ran home for it. The second time I told her she'd have to hope that daddy would be able to help her out because I wouldn't/couldn't. Daddy came to the rescue.Today, daddy is out of state and unable to help. And mommy refused to run and get it.

Honestly, my gut was to let her go hungry. I know, I am a TERRIBLE mother. But I also want her to learn that her actions have consequences. Possibly missing lunch and snack would have a positive impact on remembering her lunchbox? The teacher was not down with that idea though. We considered hot lunch but there were slim pickings for things that didn't have any allergens. I could have been mean and made her choose the one item that would have been ok from an allergy perspective but was something she doesn't enjoy eating. (Note: I'm kind of thinking I should have done this -- I just hated the idea of paying the money for hot lunch and then still not having her eat it.)

I ended up running to the New Sagaya grocery store and picking up some items for her. She'll have to do some jobs around the house to work off the cost of that lunch. I am only willing to buy one lunch a day and that was the lunch that I made for her in her lunchbox. Still, I'm feeling like she was rewarded for forgetting -- she got lunchables and all kinds of things that don't normally get packed. Maybe eating the icky bean burrito from the hot lunch menu would have had a greater impact?

So, come on readers. You're generally a quiet bunch out there but I would LOVE your recommendations. What would you do? How do you help her remember? I literally handed her the lunchbox before we left the house but it got set down to put shoes on and never returned.