Gray Grapes:

Fruit Flies is easy to play without using different colors. Keep track of whose fruit fly is whose by writing the first letter of your name as you move your fly around. Shade each grape as you go. Don't worry about covering up the letters. It isn't necessary to keep track of which grapes were eaten by which fly. The first fly to run out of grapes loses.

More Players:

Play Fruit Flies with additional players. As with the 2-player game, players should take turns moving their flies in the reverse order that they placed their flies. So, for example, if three players place flies in the order Player 1, Player 2, Player 3, then they should start moving their flies in the order Player 3, Player 2, Player 1.

Bunches of Bunches:

Start by drawing 2 separate bunches of grapes. Player 1 picks a grape bunch and places a fruit fly on it, then Player 2 places a fly on the same bunch. On the other bunch of grapes, Player 2 places their fly first, then Player 1. Once all the flies have been placed, players take turns, starting with Player 2, choosing one of their two flies to move. On your turn, you can choose either of your two flies to move. You don't necessarily need, for example, to choose a fly on the same bunch as your opponent in their previous turn. Once one of your flies is stranded, you can continue to play by moving your other fly. Play continues until one player's flies are both stranded with no more grapes to eat. The other player wins.

Strategy:

Look for opportunities to ask your child why they made the move they did, or to help them think through a move before they make it. This depends in part on counting the grapes that might be available after different moves. For example, consider the scenario below. It's Purple's move next. Which grape should they move to?

It's easy to see why the grape on the top right would be a bad idea, as the fly would then be stranded. Choosing either of the grapes on the left would eventually lead the fly down the side of the bunch where it would meet the green fly. Moving to the bottom left grape would potentially reach the bottom sooner, blocking off Green's progress. Moving to the top left grape would add a grape to the path that would be impossible to reach again later. So which is better? Here is a diagram of both possibilities (each of which assumes Green makes the logical move downward rather than getting stranded by moving up).

So moving to the bottom left grape would lead to both flies having four more grapes, and Purple being stranded on the following move. But moving to the top left grape would result in Purple having a fifth grape to eat, and Green being stranded.

Can 5 grapes be drawn so that every grape touches every other grape? Let kids try. Expand the question so that the shapes don't need to be round or resemble grapes in any way. Is it possible to draw 5 regions on a page such that each region touches each other region?

The short answer is: nope. For more information on this question, see our game Cartographer, and read about the Four Color Map Theorem.