Again, start out by planting Sun-shrooms and Puff-shrooms for basic defense and sun gathering at the beginning of the level. Plant at least three columns of Puff-shrooms and two columns of Sun-shrooms if possible.
If you are overwhelmed early on, use the Ice-shroom. It will stall the zombies for long enough to be defeated.
When your defenses become more fully developed, plant a few Repeaters for a stronger defense.
Whenever a Dancing Zombie comes, plant a Hypno-shroom for the Dancing Zombie to eat. The Dancing Zombie will then summon four Backup Dancers to fight on your side. This will also earn you the achievement Disco is Undead.
It is possible to beat this level using nothing but Puff-shrooms. This can be played for extra fun, challenge, or even both.