@DancingLeaves , wasn't me who brought up the EA2010 in the first place and I'm tempted to say, go read it yourself.
But here's a roadmap.
Protected characteristics are defined in Part 1 Chapter 1 - see clauses 4 and 10 in particular
Chapter 1
Protected characteristics
Section 4 The protected characteristics
The following characteristics are protected characteristics—
age;
disability;
gender reassignment;
marriage and civil partnership;
pregnancy and maternity;
race;
religion or belief;
sex;
sexual orientation.
Section 10. Religion or belief
(1)Religion means any religion and a reference to religion includes a reference to a lack of religion.
(2)Belief means any religious or philosophical belief and a reference to belief includes a reference to a lack of belief.
(3)In relation to the protected characteristic of religion or belief—
(a)a reference to a person who has a particular protected characteristic is a reference to a person of a particular religion or belief;
(b)a reference to persons who share a protected characteristic is a reference to persons who are of the same religion or belief.
[I think people often forget to read in lack of belief/atheism to references to "religion" when talking about the Act, because it's not what "religion" means in common parlance]
Part 1 Chapter 2 of the Act explains what constitutes prohibited conduct in relation to the protected characteristics - discrimination, harassment and victimisation.
Part 6 Chapter 1 sets out how the Act applies in education, specifically schools (other chapters in this part deal with other education settings)
Section 85 Pupils: admission and treatment, etc.
(1)The responsible body of a school to which this section applies must not discriminate against a person—
(a)in the arrangements it makes for deciding who is offered admission as a pupil;
(b)as to the terms on which it offers to admit the person as a pupil;
(c)by not admitting the person as a pupil.
(2)The responsible body of such a school must not discriminate against a pupil—
(a)in the way it provides education for the pupil;
(b)in the way it affords the pupil access to a benefit, facility or service;
(c)by not providing education for the pupil;
(d)by not affording the pupil access to a benefit, facility or service;
(e)by excluding the pupil from the school;
(f)by subjecting the pupil to any other detriment.
(3)The responsible body of such a school must not harass—
(a)a pupil;
(b)a person who has applied for admission as a pupil.
(4)The responsible body of such a school must not victimise a person—
(a)in the arrangements it makes for deciding who is offered admission as a pupil;
(b)as to the terms on which it offers to admit the person as a pupil;
(c)by not admitting the person as a pupil.
(5)The responsible body of such a school must not victimise a pupil—
(a)in the way it provides education for the pupil;
(b)in the way it affords the pupil access to a benefit, facility or service;
(c)by not providing education for the pupil;
(d)by not affording the pupil access to a benefit, facility or service;
(e)by excluding the pupil from the school;
(f)by subjecting the pupil to any other detriment.
(6)A duty to make reasonable adjustments applies to the responsible body of such a school.
(7)In relation to England and Wales, this section applies to—
(a)a school maintained by a local authority;
(b)an independent educational institution (other than a special school);
[F1(ba)an alternative provision Academy that is not an independent educational institution;]
(c)a special school (not maintained by a local authority).
Section 89 Interpretation and exceptions
(1)This section applies for the purposes of this Chapter.
(2)Nothing in this Chapter applies to anything done in connection with the content of the curriculum.
...
(12)Schedule 11 (exceptions) has effect.
If you turn to the Schedules to the Act, you will see there what exceptions are afforded to faith schools (Section 5) and all schools (Section 6).
Schedule 11 Part 2
Religious or belief-related discrimination
Section 5
Section 85(1) and (2)(a) to (d), so far as relating to religion or belief, does not apply in relation to—
(a)a school designated under section [F468A or] 69(3) of the School Standards and Framework Act 1998 (foundation or voluntary school with religious character);
(b)a school [F5(other than an alternative provision Academy)] listed in the register of independent schools for England or for Wales, if the school's entry in the register records that the school has a religious ethos;
(c)a school transferred to an education authority under section 16 of the Education (Scotland) Act 1980 (transfer of certain schools to education authorities) which is conducted in the interest of a church or denominational body;
(d)a school provided by an education authority under section 17(2) of that Act (denominational schools);
(e)a grant-aided school (within the meaning of that Act) which is conducted in the interest of a church or denominational body;
(f)a school registered in the register of independent schools for Scotland if the school admits only pupils who belong, or whose parents belong, to one or more particular denominations;
(g)a school registered in that register if the school is conducted in the interest of a church or denominational body.
Section 6
Section 85(2)(a) to (d), so far as relating to religion or belief, does not apply in relation to anything done in connection with acts of worship or other religious observance organised by or on behalf of a school (whether or not forming part of the curriculum).
The exceptions afford faith schools the ability to discriminate in relation to the protected characteristic of religion or belief (defined as including non-belief) in admissions and the way education is delivered, and (in common with all schools) in connection with acts of worship, but leaves intact the school's duty not to discriminate on the basis of religion or belief (including non-belief) in relation to exclusions or by subjecting pupils to any other detriment.
The exceptions also leave intact the school's duty not to harass pupils on the basis of their religion or belief (including non-belief) - what constitutes harassment is set out in Part 1Chapter 2 section 26:
1)A person (A) harasses another (B) if—
(a)A engages in unwanted conduct related to a relevant protected characteristic, and
(b)the conduct has the purpose or effect of—
(i)violating B's dignity, or
(ii)creating an intimidating, hostile, degrading, humiliating or offensive environment for B.
Victimisation would be subjecting a person to a detriment because they make an allegation or claim (same chapter as above, clause 27).
If you've made it this far, I hope that assisted in clarifying.