Yes, "Students is" is really wrong, if "Students" is plural, but there may be cases where "Students" can be treated as singular (see below).
Subject-Verb agreement in general
The subject and verb must agree. Since "is" is singular, it must be preceded by a singular subject.
As YourDictionary puts it:
Subject verb agreement simply means the subject and verb must agree in number. This means both need to be singular or both need to be plural.
Cases where the subject can be treated as singular
There are cases where the subject may appear to be plural at first glance, but is really singular (or can be).
a) Compound Nouns: As we see in Rule 4 in grammarbook
Rule 4. As a general rule, use a plural verb with two or more subjects when they are connected by and.
Example: A car and a bike are my means of transportation.
But note these exceptions:
- Breaking and entering is against the law.
- The bed and breakfast was charming.
In those sentences, breaking and entering and bed and breakfast are compound nouns.
The examples from Edwin Ashworth (bacons and eggs, and health and safety) are compound nouns.
b) Collective Nouns: As we see in Rule 9 in grammarbook
Rule 9. With collective nouns such as group, jury, family, audience, population, the verb might be singular or plural, depending on the writer's intent.
- All of my family has arrived OR have arrived.
- Most of the jury is here OR are here.
- A third of the population was opposed OR were opposed to the bill.
By this rule, the word "students" could be singular or plural, depending on the writer's intent.
- If "students" is a group/category, where other groups may be "teachers", "parents" and so on, then it would be singular, so your sentence would be grammatically correct.
- If "students" is treated as plural (referring to them as multiple individuals), then your sentence should use "are".