With the Covid-19 pandemic and its attendant devastating effects that have hampered every aspect of human existence; it becomes pertinent on the government, stakeholders, and the academia to invigorate possible measures to mitigate the impact of the pandemic as it relates to teaching and learning; considering curtailing measures of the pandemic that restricted human contacts and social gatherings; hence the adoption of ICT by schools for teaching and learning. This is what necessitated this study, to ascertain the effect of ICT adoption in Nigerian schools in the post Covid-19 era. The study explored the purposive sampling technique of data collection. A wellstructured questionnaire was distributed to 250 students and 50 lecturers, selected from 5 chosen private universities in South-East Nigeria. The reliability of the instrument was determined using the Cronbach’s Alpha coefficient. The study applied the mean, standard deviation, and the Pearson’s Correlation for data Analysis. The result revealed that ICT adoption has a significant positive effect on effective teaching and learning through the provision of various ICT tools in the post Covid-19 era in Nigeria; significant positive effect in mitigating the problems of Students-Teacher ratio (mostly in overcrowded classes), and also a significant positive effect in influencing teacher subjectmatter mastery and lesson preparedness. In furtherance, the result revealed that ICT adoption in schools has no significant effect on effective classroom management (through internal learning distractors’ mitigation), and also no significant effect on education affordability (through cost implication reduction). The study concluded that ICT adoption in schools, on the average, will influence effective teaching and learning in the post Covid-19 Nigeria to a high extent, and recommended among others the need for curriculum review by the Nigerian Government for ICT inclusion, to achieve effective teaching and learning in schools in the post Covid-19 Nigeria.