OPINION BY
STEVENS, J.:¶ 1 Defendant Jeffrey Teeter appeals from the judgment of sentence entered after a jury convicted him of possession with intent to deliver cocaine (“PWID”), criminal use of a communication facility, possession of a controlled substance, corruption of minors, and possession of drug paraphernalia, charges stemming from his intended sale of drugs at the residential driveway of a 17-year-old buyer. Sentenced to not less than three years or more than six years’ incarceration on PWID,1 Teeter first claims the trial court erred in imposing an additional two year mandatory sentence under 18 Pa.C.S.A. § 6314(b)(4),2 a sentencing enhancement for selling drugs within 500 feet of a school bus stop. His second claim challenges the denial of his pretrial motion to suppress evidence obtained from a vehicle search he contends was performed without either probable cause or his voluntary consent. We affirm.
¶2 On the evening of June 7, 2004, Teeter made a telephone call to set up a drug sale to S.F., a 17-year-old girl. S.F. asked Teeter to bring the “powder” to her house; he agreed. Unbeknownst to either of them, S.F.’s father was listening in on another telephone extension. Suspecting his daughter’s imminent involvement in drug activity, Father called the police and requested their presence. Father explained to the police dispatcher that his daughter had agreed to purchase drugs from the subject on the other end of the telephone and that this person was on his way to his residence. At the conclusion of his telephone conversation, Father stated that an unfamiliar vehicle was pulling into his driveway, and he believed this to be the person coming to sell drugs. Teeter was the driver of that car.
¶ 3 Teeter and a companion parked in Father’s driveway and S.F. walked out to meet them. S.F. and Teeter spoke, but the drug transaction did not occur. At approximately 9:40 p.m., with Teeter still parked in Father’s driveway, two state police troopers pulled up and parked their cruisers in the lane leading to the driveway. A few minutes later a police corporal *894arrived on the scene and parked his cruiser in the lane. At all times, adequate space remained for Teeter to drive his car past the officers and their cruisers.
¶ 4 With Teeter and his companion standing outside of Teeter’s car, one trooper asked Teeter why he was there. He told the trooper that he was there to collect money he was owed for selling stereo equipment. Another trooper asked the same question of Teeter’s companion while the corporal talked to Father. All of these events in the driveway occurred within twenty minutes, at which point the officers decided to request consent to search Teeter’s vehicle. A Waiver of Rights/Consent to Search form was read in its entirety to Teeter, following which he consented and signed the form. When asked, Teeter indicated that he was the owner of the car and all its contents except for a cell phone.
¶ 5 At that point Teeter lunged into the open driver’s side window, where officers witnessed him reach out his hand and brush a clear plastic baggie containing a white powdery substance off of the seat of the vehicle. After claiming that he had nothing to hide, Teeter reached into his front jeans’ pockets and turned them inside out; however, one of the troopers noticed he was concealing a marijuana pipe in his hand. The officers took custody of the pipe and the clear plastic baggie and then gave Teeter his Miranda3 warnings. Teeter signed a waiver in the presence of two officers.
¶ 6 Teeter confessed that he had called and set up the deal to sell cocaine to S.F. He explained that since she could not leave her house, he went to her residence to conduct the drug sale. Since Father was keeping a watchful eye from the garage, Teeter and S.F. had decided to forego the drug deal. Teeter also volunteered to the police that there was a second baggie of cocaine along with a plastic cut-off straw in his car. When the officers could not find it, he also assisted them in locating it in a felt box hidden under the driver’s side seat cushion.
¶ 7 In the days following Teeter’s arrest, it was determined that Teeter intended to sell drugs to S.F. ninety-two feet from a location designated by the local public school district as a school bus stop. The Commonwealth therefore notified Teeter after his conviction that it would seek the mandatory three-year minimum sentence under section 6314(b)(4).
¶ 8 At sentencing, the Commonwealth presented the testimony of, inter alia, a school bus driver for the Chestnut Ridge School District.4 She testified that the school district has charted the school bus stop in question on her designated route for “probably ten years,” that the stop was so designated on June 7, 2004, and remained so designated without interruption on the day of her testimony. N.T. Sentencing Hearing, 7/11/05 at 15, 17-18. Moreover, when defense counsel asked her if it was true that school bus stops may change from time to time because of “traffic and whatever,” the driver replied “Yes, I would imagine, [b]ut that stop don’t change.” N.T. at 17-18.
¶ 9 The sentencing court viewed the evidence in light of the language of Section 6314(b)(4) and rejected Teeter’s argument *895that the bus stop was not a bus stop on the summer night in question because school was out of session. Specifically, the court opined at one point “the legislation just says a school bus stop. It doesn’t say anything about this and I’m satisfied it is a school bus stop.... ” N.T. at 9.
¶ 10 On appeal, Teeter first argues he cannot be subject to the mandatory minimum penalty under Section 6314(b)(4)5 for a drug offense committed against a minor within 500 feet of a school bus stop because his conduct occurred at a time when school was out of session and children were not present. Specifically, he argues the phrase “school bus stop” as used in Section 6314(b)(4) is impermissibly vague and that the statute is thus vague and overbroad.
¶ 11 A defendant does have a substantive due process right to be free from vague and overbroad sentencing statutes. Commonwealth v. Johnson, 572 Pa. 283, 815 A.2d 563 (2002); Commonwealth v. Bell, 537 Pa. 558, 645 A.2d 211 (1994); Commonwealth v. Burnsworth, 543 Pa. 18, 669 A.2d 883 (1995). This due process right is connected to the right to be free from arbitrary or discriminatory sentencing. Bell at 567 n. 9, 645 A.2d at 216 n. 9. When faced with such a challenge, courts must define the allegedly-vague word or phrase to determine its meaning, in keeping with the apparent intent of the General Assembly (as discussed infra) Burnsworth. However, since the sentencing enhancement does not apply until sentencing, notice of its application is not required until after the defendant is tried and convicted of the underlying crime. See Commonwealth v. Grundy, 385 Pa.Super. 384, 561 A.2d 39, 40 (1989) (citing Commonwealth v. Bell, 512 Pa. 334, 516 A.2d 1172 (1986)).
¶ 12 The legislature has the authority to enact sentencing schemes that reflect various penal philosophies, including other recognized goals of sentencing beyond individual deterrence and rehabilitation, such as retribution and vindication. Commonwealth v. Vasquez, 562 Pa. 120, 127-128, 753 A.2d 807, 811 (2000) (Cappy, Justice, concurring). The legislative policy behind Chapter 63 and its enhancement penalties is to punish more severely those who seek to involve children with drugs. Commonwealth v. Hinds, 775 A.2d 859, 863 (Pa.Super.2001) (en banc), appeal denied, 567 Pa. 757, 790 A.2d 1014 (2001) (interpreting Section 6317 of the Crimes Code, “Drug-Free School Zones,” as intended to protect young children from illegal activity attendant with the drug trade, whether or not children were present or had access to the drugs).
¶ 13 As discussed infra, we conclude the phrase “school bus stop” is unambiguous under the facts presented at sentencing in the case sub judice. A plain reading of Section 6314(b)(4) yields no ambiguity within the statute and reveals a legislative intent to regulate sentences for drug offenses committed near places used as school bus stops. Specifically, the Commonwealth established at sentencing that the crime of PWID for which Teeter was convicted occurred within 500 feet of a long-standing designated school bus stop. The Commonwealth thus met its burden under the sentencing statute, which bound *896the trial court to add, as it did, two years to Teeter’s minimum sentence.
¶ 14 Teeter argues that the phrase “school bus stop” is impermissibly vague under the facts. Without a permanent landmark signifying its use, Teeter claims, the location in question is a school bus stop only when children are gathered there either before boarding or after exiting a school bus. As school was out of session for summer break when he committed the underlying offense, Teeter concludes there was no school bus stop nearby to bring him under the statute.6
¶ 15 “A lawfully enacted statute commands a presumption of constitutionality and should be upheld unless it clearly, palpably, and plainly violates the constitution.” Bell, 537 Pa. at 569, 645 A.2d at 217. One has a constitutional right to be free from vague and overbroad sentencing statutes. Johnson, supra. The due process right is connected to the right to be free from arbitrary or discriminatory sentencing. Bell at 567 n. 9, 645 A.2d at 216 n. 9. Where a facial attack on the alleged vagueness of a statute does not implicate First Amendment freedoms, we measure the specificity of a statute against the actual conduct in which the appellant engaged. Commonwealth v. Wallace, 368 Pa.Super. 255, 533 A.2d 1051, 1052 (1987).
¶ 16 In construing the enactments of the legislature, appellate courts must refer to the provisions of the Statutory Construction Act. Commonwealth v. Campbell, 758 A.2d 1231 (Pa.Super.2000). In so doing, we are obliged to consider the intent of the legislature and give effect to that intention. Id. The General Assembly has clarified the approach we are to use to determine legislative intent as follows:
(a) The object of all interpretation and construction of statutes is to ascertain and effectuate the intention of the General Assembly. Every statute shall be construed, if possible, to give effect to all its provisions.
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(c) When the words of the statute are not explicit, the intention of the General Assembly may be ascertained by considering, among other matters:
(1) The occasion and necessity for the statute.
(2) The circumstances under which it was enacted.
(3) The mischief to be remedied.
(4) The object to be attained.
(5) The former law, if any, including other statutes upon the same or similar subjects.
(6) The consequences of a particular interpretation.
(7) The contemporaneous legislative history.
(8) Legislative and administrative interpretations of such statute.
1 Pa.C.S.A. § 1921.
¶ 17 We are to give words in a statute their plain and ordinary meaning, and construe them according to their common and accepted usage. Campbell, supra; 1 Pa.C.S.A. § 1903. We may not add *897provisions or impose restrictions that the General Assembly has omitted unless necessary to the construction of the statute. Id. In determining the need for an addition, we remain mindful that such addition may “not conflict with the obvious purpose and intent of the statute.” Id. at 1234 (quoting Commonwealth v. Fisher, 485 Pa. 8, 13, 400 A.2d 1284, 1287) (1979); 1 Pa. C.S.A. § 1923(c). As such, statutory words are to be read in the context of the whole statute, whose every word, sentence, and provision have some purpose which this Court must give effect. Campbell at 1234.
¶ 18 Moreover:
[A] penal statute is a statute that defines criminal offenses and specifies corresponding fines and punishment. Penal statutes must be strictly construed. Strict construction does not require that the words of a criminal statute be given their narrowest meaning or that the Legislature’s evident intent be disregarded. Language which is capable of more than one meaning can be clear and unmistakable in the context of its usage by the selection of the meaning which is neither forced nor strained.
Id. at 1236-37.
¶ 19 We must, therefore, determine the meaning of “school bus stop” in keeping with the apparent intent of the General Assembly. “18 Pa.C.S.A. § 6314. Sentencing and penalties for trafficking drugs to minors” provides that a person 18 years or older convicted of delivering or possessing with the intent to deliver drugs to a minor be sentenced to a minimum sentence of at least one year incarceration. 18 Pa.C.S.A. § 6314(a). The statute further mandates that an additional minimum sentence of at least two years be imposed if, inter alia, the offense occurred within 1,000 feet of a school, per Section 6314(b)(3), or, pertinent here, “within 500 feet of a school bus stop,” per Section 6314(b)(4). Section 6314(c), moreover, addresses due process rights by explaining that the provisions of the sentencing statute are not elements of the underlying drug offenses themselves, and that a defendant need not receive notice of their applicability until after he is convicted of a qualifying offense. See Vasquez, supra (Cappy, J. concurring) (reiterating goals of sentencing unrelated to deterrence).
¶ 20 Teeter asserts that an officially designated school bus stop is not a “school bus stop” as provided in Section 6314(b)(4) unless children are actually there waiting for a bus. This restrictive interpretation is at odds with a plain reading of the statute, the obvious purpose of the protective statutory scheme of which Section 6314 is a part, and with our jurisprudence interpreting companion sections within that scheme.
¶ 21 Applying a plain meaning analysis to Section 6314(b)(4), the phrase “school bus stop” is an unambiguous, commonly understood phrase meaning a place where children are to board and exit a school bus. Notably, the statute contains no modifying language placing time limitations on the phrase. As recited supra in the standard of review governing statutory interpretation, we may not read unexpressed restrictions and limitations into a statute unless it is necessary to give it its proper construction in light of clear legislative intent.
¶ 22 Thus, the phrase “school bus stop” is clear and is consistent with the apparent intent of the General Assembly to punish more severely those who seek to involve children with drugs. The legislature has made the policy decision to keep safe and drug-free, to the greatest extent possible, neighborhoods immediately surrounding our schools, playgrounds, and school bus stops on a year-round basis, even at times *898when schools are not in session. The legislative purpose in continuously protecting our school-age children from drug dealers, addicts, gangs, and their nefarious activities is no less constitutionally permissible when applied to school bus stops than it is for schools and playgrounds.
¶ 23 The intended purpose of the statutory scheme, therefore, is the continuous protection of places where we direct our children to gather regularly at certain times of the year. For the courts to relax or suspend altogether our application of sentencing enhancements during times at which such places are not in use makes it more likely for the drug trade and its attendant vices to gain a foothold near those places in which the legislature created safe havens. For this Court to encourage the decline of neighborhoods enveloping school bus stops so as to compromise the safety of children gathering there during the school year would certainly frustrate the clear and compelling legislative intent underlying the entire statutory scheme.
¶ 24 Our decision here is consistent with the manner in which we applied a strict interpretation of Section 6317, Drug free school zones. In a series of decisions, we held that mandatory minimum sentence provisions applied when defendants were convicted for selling drugs near schools and playgrounds even when: (1) no children were involved in the transaction; (2) the playground was on private property; (3) the transaction took place in a residence not accessible to the public; and/or (4) when school was not in session. See Commonwealth v. Williams, 955 A.2d 386, 2008 Pa. Super Lexis 2042 (Pa.Super.2008); Commonwealth v. Hinds, 775 A.2d 859 (Pa.Super.2001) (en banc); Commonwealth v. Drummond, 775 A.2d 849 (Pa.Super.2001) (en banc); and Campbell, supra. Acknowledged in these decisions was the legitimate and paramount legislative intent to “fortify the barrier that segregates the places where our children frequent from the illegal drug scene.” Campbell at 1236-1237; Hinds at 862 (quoting Campbell, supra); Drummond at 856 (quoting Campbell, supra). It follows that to keep such places free from the ravages of drugs, the legislature intended extensive and continuous application of the sentencing enhancement statute.7 For the same reasons, therefore, we would hold that within the plain meaning of a “school bus stop” is the fact that it exists regardless of whether school is in session.
¶ 25 Here it is undisputed that Teeter chose to deliver cocaine to a school-age minor 92 feet from a location officially designated a school bus stop for the past ten years. Moreover, there is nothing in the record to indicate that the stop had lost its status as a school bus stop. As such, there is no merit to Teeter’s claim that Section 6314(b)(4) is impermissibly vague under the facts presented at sentencing so as to prevent application of the sentencing enhancement therein.
¶ 26 Next, Teeter contends that from the time the police arrived at Father’s residence he was the subject of an illegal arrest and, as such, all evidence discovered by the police should have been suppressed before trial. It was unreasonable, he contends, to believe he was free to leave when officers were on each side of *899his car with their cruisers parked behind him. This argument fails.
¶ 27 An encounter between police and a suspect may be characterized as a mere encounter, an investigative detention, a custodial detention, or a formal arrest. Commonwealth v. Douglass, 372 Pa.Super. 227, 539 A.2d 412, 417 (1988). Since a mere encounter carries no official compulsion to stop or respond, it need not be supported by any level of suspicion. Meanwhile, an investigative detention must be supported by reasonable suspicion since it subjects the suspect to a stop and a period of detention. However, unlike a custodial detention or a formal arrest, an investigative detention does not require probable cause because it lacks the same magnitude of coercive conditions. Id. at 418. The court considers the totality of the circumstances to determine if an encounter is investigatory or custodial, but the following factors are specifically considered: the basis for the detention; the duration; the location; whether the suspect was transported against his will, how far, and why; whether restraints were used; the show, threat or use of force; and the methods of investigation used to confirm or dispel suspicions. Id. at 421.
¶ 28 In the present case, the officers responded to a call that someone unknown to Father was coming to his residence to sell drugs to his minor daughter. Shortly thereafter, when an unfamiliar car pulled into Father’s driveway and parked, police officers suspected the driver of that vehicle was the unknown person. These facts created at least reasonable suspicion that Teeter was the one intending to engage in criminal activity at Father’s residence. Once the police arrived on the scene, they talked to Teeter for 20 minutes. Teeter was never prevented from leaving the residence, nor was he told by the officers that he was not free to leave. The officers did not use any restraints or any threat of force on Teeter, but, rather, the officers simply asked Teeter questions and requested information. We agree with the trial court that up to the point that the police administered Miranda warnings to Teeter, the police encounter with Teeter amounted to no more than an investigative detention. He was never detained or arrested and, thus, the trial judge was correct to deny Teeter’s motion to suppress. Accordingly, we reject Teeter’s challenge to the order denying his motion to suppress.
¶ 29 Judgment of sentence is affirmed.
¶ 30 Judge KLEIN files a Concurring and Dissenting Opinion in which Judge BENDER and Judge BOWES join.
. 35 P.S. § 780-113(a)(30).
. Section 6314(b) provides:
§ 6314. Sentencing and penalties for trafficking drugs to minors
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(b) Additional penalties. — In addition to the mandatory minimum sentence set forth in subsection (a), the person shall be sentenced to an additional minimum sentence of at least two years total confinement, notwithstanding any other provision of this title or other statute to the contrary, if the person did any of the following:
(1) Committed the offense with the intent to promote the habitual use of the controlled substance.
(2) Intended to engage the minor in the trafficking, transportation, delivery, manufacturing, sale or conveyance.
(3) Committed the offense within 1,000 feet of the real property on which is located a public, private or parochial school or a college or university.
(4) Committed the offense on a school bus or within 500 feet of a school bus stop.
18 Pa.C.S.A. § 6314 (emphasis added).
. Miranda v. Arizona, 384 U.S. 436, 86 S.Ct. 1602, 16 L.Ed.2d 694 (1966).
. Also testifying were S.F.'s father and Pennsylvania State Police Trooper Corporal Bradley Hershey, who testified he measured the distance between the bus stop and the residence after being told the location where the minor and defendant were standing. He also verified the location of the school bus stop with the school bus driver. N.T. Sentencing Hearing, 7/11/2005, at 21-22.
. We note that challenges to a trial court's application of a mandatory sentencing provision implicate the legality of sentence. Commonwealth v. Bongiorno, 905 A.2d 998 (Pa.Super.2006) (en banc), citing Commonwealth v. Lewis, 885 A.2d 51, 55 (Pa.Super.2005). Issues relating to the legality of a sentence are questions of law, as are claims concerning the court’s application of a statute. Id. As such, our scope of review is plenary. Lewis, supra.
. Appellant offers an alternate overbreadth challenge that if “school bus stop” as provided in Section 6314(b) applies even when children are absent from such locations, then the statute impermissibly implicates conduct irrelevant to the intent of the General Assembly to keep drugs from children's midst. As explained infra, however, Section 6314(b)(4) and its provision of a 500 foot zone is rationally related to the clear legislative intent to fortify the barrier segregating the drug trade from places where our children routinely gather.
. In Drummond, for example, the defendant argued the word “zone” in Section 6317 bore a rational relationship to the legitimate legislative intent of protecting children from the drug trade only so long as its definition was restricted to mean public places accessible by children. In rejecting this argument, we reiterated the legislature’s legitimate and broad goal of protecting children not only from direct drug solicitations but also from all nefarious consequences of the drug trade. Drummond at 855.