Teachers will walk out for 16 days in January and February in an escalation in the union's standoff with the Scottish Government and councils.
The Educational Institute of Scotland (EIS) said action will take place over 16 consecutive days in January and February, with teachers in two local authorities walking out each day.
The action will start - unless a deal is agreed before then - on January 16 and is due to last until February 6.
General secretary Andrea Bradley praised the teachers who took part in the first strike on Thursday, saying they had been angered by the conduct of the Scottish Government and local authority body Cosla in presenting their latest offer.
National strike days will also take place on January 10 for teachers in primary and special schools, as well as early years, and on January 11 for those working in secondary schools and secondary special schools.
Announcing the latest action, Ms Bradley said: "The EIS will move ahead with our previously announced two additional days of national strike action in January.
"We can also now confirm that Scotland's teachers will strike on 16 consecutive days in January and February, with teachers in two local authorities on strike on each of these 16 days.
"We have been forced into the escalation of this action by the lack of willingness to negotiate properly and to pay teachers properly, by a Government that says it wished to be judged on its record on education.
"The judgment of Scotland's teachers on the matter of pay is clear, with the first programme of national strike action that we have engaged in for four decades.
"It is now for the Scottish Government and Cosla to resolve this dispute, and prevent further strike action, by coming back to the negotiating table with a substantially improved pay offer for all of Scotland's teaching professionals."
The Scottish Government submitted a pay offer to teachers earlier this week which was summarily dismissed by the unions.
Under that proposal, teachers earning under £40,107 would receive an increase of £1,926 per year - 6.85% for those on the lowest salaries - while those on more would get 5%.
The Government has insisted it has no more cash for pay offers, with Scottish Education Secretary Shirley-Anne Somerville saying any increase in funding would have to come from elsewhere in the budget.
The EIS has been pushing for a minimum of a 10% increase.
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