Playa Norte on Isla Mujeres is the best family beach - shallow water, soft sand, and beach clubs that welcome kids instead of treating them like noisy interruptions.

Take ferry from Puerto Juárez (cheaper than Hotel Zone departure). Kids under 4 usually free but bring ID.

Hotel Zone beaches: Playa Norte near Sheraton has lifeguards and gentle waves. Avoid Playa Chac Mool - too crowded and aggressive vendors. Playa Delfines has space but currents too strong for little ones.

Pro tip: Bring pop-up tent from home. Beach umbrella rental is $20+ daily and they're flimsy. Saved our sanity with three kids under 10.