Who doesn't love Legos? I mean, they're the gift that keeps on giving, put them together, play, leave them out for a few days, put them away and rediscover them again a few days later. My boys, ages 4 & 6 are obsessed with their Dino Valley Duplo set. This is literally one of the very few toys that does not initiate fights. Their cooperative play is unbelievable with this set. I LOVE that the instructions are easy enough for my oldest to understand and he helps my little one put together the entire set. Set up takes them about 15 minutes, but then they will play for at least an hour! It cracks me up listening to them. I mean the "cavemen" are having dino races, the dinos are cooking up some dinner, and everyone naps around the "fire." I've actually sat down and joined in several times. You should hear their cavemen bedtime stories! It's a great time and their creativity just blows me away. The set is so detailed, everything from the steak to the "fur" blankets makes Dino Valley the ultimate gift for kids ages 3-6. Just for boys? No way, we recently had a party at our home and the little girls loved playing with it too.