The 7-year-old boy wins this round against the lightweight BMW i3.

We're not sure if this is a BEV i3 or REx i3, but either way the i3 is so lightweight that, if need be, your 7-year-old could probably push it.

Don't try this with a Tesla Model S.

At 2,635 (BEV) to 2,800 (REx) pounds the i3 is one of the lightest cars on the market, which makes for an agile, quick vehicle that easily pushed too.  That's a useful attribute for those rare occasions when you run completely out of charge within feet of your driveway.