The following ESL resources are available for Zero conditional:
More challenging conditionals dominoes matching activity for all conditionals (zero - third) + conditional structures without 'if'.
Cut-up sentences: first, second and open conditionals.
Cut-up sentences: first, second, third and open conditionals.
(1) Seven pairs of sentences. Ss have to differentiate between those that are generally true and those that refer to a probable sitution in the future. (2) Personalization. Five questions with prompts that produce first or zero conditional answers. (Some HK references)
Similar to Conditional dominoes 1 (the first and second conditional examples are the same) but with zero conditional substituted for third.