I showed him the "parking lot" with spots for 14 cars and told him he would be practicing parking his cars, but that they had to match the cards.
I set out the number line for him to use if he needed help identifying the number, then had him pick a card. He could then see how many cars he was to park, as well as what colors the cars needed to be. It was up to him as to how many cars of each color to use. It ended up being a lesson in addition as well with things like, "how many orange cars did you choose?...4... How many blue cars?...3...So 4 plus 3 equals...?" It was easy to set up, educational, and he really enjoyed it. Plus, it was something that once he got the hang of it he really didn't need me to be very involved other than to affirm that what he did was correct. Definitely a keeper for us!