An hypothesis is a preliminary or tentative explanation or postulate by the researcher of what the researcher considers the outcome of an investigation will be. It is an informed/educated guess.

7. Hypothesis
Can be tested
and
verified
Suggested
solution to a
problem
Problem
Formulated in the
Origin from which
an hypothesis
is derived
form of a
question

9. But not all if-then statements are hypotheses.

17. How to Create a Hypothesis

18. Null Form
Declarative
form
Question
form
Prediction
form

19. There is significant difference between the academic achievement of
XIIth standard students in control group and experimental group.
There is no significant difference between the academic achievement
of XIIth standard students in control group and experimental group.
Is there significant difference between the academic achievement of
XIIth standard students in control group and experimental group.
The students will memorize definitions better if teacher introduces
appropriate memory techniques.

21. Importance of
hypothesis

22. Difficulties in the formulation of hypothesis

26. There is no significant difference between the performance of standard IX students with
respect to the variable Medium
Variable Test Group Category No Mean S.D ‘t’
Value
Table
Value
Result
Medium of
Study
Pre Test
Tamil
CG
10 43.5 9.732
1.04569
1.96
NS
EG
4 50 10.800
English
CG
20 41.25 13.752
0.181251 NS
EG 26 40.576 10.613
Post Test
Tamil
CG
10 41 10.488
6.23083
1.96
S
EG
4 81.25 11.086
English
CG
20 48.75 9.013
10.6723 S
EG 26 79.615 10.575
NS  Not Significant  Null Hypothesis Accepted
S  Significant  Null Hypothesis Rejected
In the control group, the hypothesis is accepted since the table value is greater than the calculated value.
This means that medium has no influence on the achievement of standard IX students in their science subject.
But in the experimental group, the hypothesis is rejected since the table value is less than the calculated value.
This shows that medium influences the academic achievement of standard IX students in their science subject.